Revert of Remove the top-level GYP files (or stub them out).

build/common.gypi

+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# IMPORTANT:
+# Please don't directly include this file if you are building via gyp_chromium,
+# since gyp_chromium is automatically forcing its inclusion.
+{
+  # Variables expected to be overriden on the GYP command line (-D) or by
+  # ~/.gyp/include.gypi.
+  'variables': {
+    # Putting a variables dict inside another variables dict looks kind of
+    # weird.  This is done so that 'host_arch', 'chromeos', etc are defined as
+    # variables within the outer variables dict here.  This is necessary
+    # to get these variables defined for the conditions within this variables
+    # dict that operate on these variables.
+    'variables': {
+      'variables': {
+        'variables': {
+          'variables': {
+            # Whether we're building a ChromeOS build.
+            'chromeos%': 0,
+
+            # Whether we're building the cast (chromecast) shell
+            'chromecast%': 0,
+
+            # Whether or not we are using the Aura windowing framework.
+            'use_aura%': 0,
+
+            # Whether or not we are building the Ash shell.
+            'use_ash%': 0,
+
+            # Whether or not we are using CRAS, the ChromeOS Audio Server.
+            'use_cras%': 0,
+
+            # Use a raw surface abstraction.
+            'use_ozone%': 0,
+
+            # Configure the build for small devices. See crbug.com/318413
+            'embedded%': 0,
+
+            'conditions': [
+              # Compute the architecture that we're building on.
+              ['OS=="win" or OS=="ios"', {
+                'host_arch%': 'ia32',
+              }, {
+                'host_arch%': '<!pymod_do_main(detect_host_arch)',
+              }],
+            ],
+          },
+          # Copy conditionally-set variables out one scope.
+          'chromeos%': '<(chromeos)',
+          'chromecast%': '<(chromecast)',
+          'use_aura%': '<(use_aura)',
+          'use_ash%': '<(use_ash)',
+          'use_cras%': '<(use_cras)',
+          'use_ozone%': '<(use_ozone)',
+          'embedded%': '<(embedded)',
+          'host_arch%': '<(host_arch)',
+
+          # Whether we are using Views Toolkit
+          'toolkit_views%': 0,
+
+          # Use the PCI lib to collect GPU information.
+          'use_libpci%': 1,
+
+          # Use OpenSSL for representing certificates. When targeting Android,
+          # the platform certificate library is used for certificate
+          # verification. On other targets, this flag also enables OpenSSL for
+          # certificate verification, but this configuration is unsupported.
+          'use_openssl_certs%': 0,
+
+          # Whether or not we use external popup menu.
+          'use_external_popup_menu%': 0,
+
+          # Disable viewport meta tag by default.
+          'enable_viewport%': 0,
+
+          # Enable HiDPI support.
+          'enable_hidpi%': 0,
+
+          # Enable Wayland display server support.
+          'enable_wayland_server%' : 0,
+
+          # Enable Wi-Fi Display support.
+          # WARNING: This enables MPEG Transport Stream (MPEG-TS) encoding!
+          'enable_wifi_display%' : 0,
+
+          # By default we build against a stable sysroot image to avoid
+          # depending on the packages installed on the local machine. Set this
+          # to 0 to build against locally installed headers and libraries (e.g.
+          # if packaging for a linux distro)
+          'use_sysroot%': 1,
+
+          # Override buildtype to select the desired build flavor.
+          # Dev - everyday build for development/testing
+          # Official - release build (generally implies additional processing)
+          # TODO(mmoss) Once 'buildtype' is fully supported (e.g. Windows gyp
+          # conversion is done), some of the things which are now controlled by
+          # 'branding', such as symbol generation, will need to be refactored
+          # based on 'buildtype' (i.e. we don't care about saving symbols for
+          # non-Official # builds).
+          'buildtype%': 'Dev',
+
+          # Override branding to select the desired branding flavor.
+          'branding%': 'Chromium',
+
+          'conditions': [
+            # Windows and Linux use Aura, but not Ash.
+            ['OS=="win" or OS=="linux" or OS=="openbsd" or OS=="freebsd"', {
+              'use_aura%': 1,
+            }],
+
+            # ChromeOS uses Ash.
+            ['chromeos', {
+              'use_ash%': 1,
+            }],
+
+            ['chromecast==1', {
+              'use_libpci': 0,
+              'conditions': [
+                ['OS!="android"', {
+                  'embedded%': 1,
+                  'use_ozone%': 1,
+                }],
+              ],
+            }],
+
+            # Ozone uses Aura.
+            ['use_ozone==1', {
+              'use_aura%': 1,
+            }],
+
+            # Whether we're a traditional desktop unix.
+            ['(OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris") and chromeos==0', {
+              'desktop_linux%': 1,
+            }, {
+              'desktop_linux%': 0,
+            }],
+
+            # Embedded implies ozone.
+            ['embedded==1', {
+              'use_ozone%': 1,
+            }],
+
+            # Mac and Android use external popup menu.
+            ['OS=="mac" or OS=="android"', {
+              'use_external_popup_menu%': 1,
+            }],
+
+            ['OS=="android"', {
+              'target_arch%': 'arm',
+            }, {
+              # Default architecture we're building for is the architecture we're
+              # building on, and possibly sub-architecture (for iOS builds).
+              'target_arch%': '<(host_arch)',
+            }],
+          ],
+        },
+        # Copy conditionally-set variables out one scope.
+        'chromeos%': '<(chromeos)',
+        'chromecast%': '<(chromecast)',
+        'desktop_linux%': '<(desktop_linux)',
+        'use_aura%': '<(use_aura)',
+        'use_ash%': '<(use_ash)',
+        'use_cras%': '<(use_cras)',
+        'use_ozone%': '<(use_ozone)',
+        'embedded%': '<(embedded)',
+        'use_libpci%': '<(use_libpci)',
+        'use_openssl_certs%': '<(use_openssl_certs)',
+        'use_external_popup_menu%': '<(use_external_popup_menu)',
+        'enable_viewport%': '<(enable_viewport)',
+        'enable_hidpi%': '<(enable_hidpi)',
+        'enable_wayland_server%': '<(enable_wayland_server)',
+        'enable_wifi_display%': '<(enable_wifi_display)',
+        'buildtype%': '<(buildtype)',
+        'branding%': '<(branding)',
+        'branding_path_component%': '<(branding)',
+        'host_arch%': '<(host_arch)',
+        'target_arch%': '<(target_arch)',
+        'use_sysroot%': '<(use_sysroot)',
+
+        # Set to true to instrument the code with function call logger.
+        # See src/third_party/cygprofile/cyg-profile.cc for details.
+        'order_profiling%': 0,
+
+        'target_subarch%': '',
+
+        # The channel to build on Android: stable, beta, dev, canary, or
+        # default. "default" should be used on non-official builds.
+        'android_channel%': 'default',
+
+        # Set ARM architecture version.
+        'arm_version%': 7,
+
+        # Use aurax11 for clipboard implementation. This is true on linux_aura.
+        'use_clipboard_aurax11%': 0,
+
+        # goma settings.
+        # 1 to use goma.
+        # If no gomadir is set, it uses the default gomadir.
+        'use_goma%': 0,
+        'gomadir%': '',
+
+        'chroot_cmd%': '',
+
+        # The system libdir used for this ABI.
+        'system_libdir%': 'lib',
+
+        # Default MIPS arch variant. This is set in the conditions block
+        # below for MIPS targets.
+        'mips_arch_variant%': '',
+
+        # MIPS DSP ASE revision. Possible values are:
+        #   0: unavailable
+        #   1: revision 1
+        #   2: revision 2
+        'mips_dsp_rev%': 0,
+
+        # MIPS SIMD Arch compilation flag.
+        'mips_msa%': 1,
+
+        'conditions': [
+          ['branding == "Chrome"', {
+            'branding_path_component%': 'google_chrome',
+          }],
+
+          ['branding == "Chromium"', {
+            'branding_path_component%': 'chromium',
+          }],
+
+          # Ash needs Aura.
+          ['use_aura==0', {
+            'use_ash%': 0,
+          }],
+
+          # Set default value of toolkit_views based on OS.
+          ['OS=="mac" or OS=="win" or chromeos==1 or use_aura==1', {
+            'toolkit_views%': 1,
+          }, {
+            'toolkit_views%': 0,
+          }],
+
+          # Embedded builds use aura without ash or views.
+          ['embedded==1', {
+            'use_aura%': 1,
+            'use_ash%': 0,
+            'toolkit_views%': 0,
+          }],
+
+          # Chromecast builds on x86 Linux should default to desktop builds.
+          ['chromecast==1 and OS=="linux" and (target_arch=="ia32" or target_arch=="x64")', {
+            'is_cast_desktop_build%': 1,
+          }, {
+            'is_cast_desktop_build%': 0,
+          }],
+
+          # Enable HiDPI on Mac OS, Windows and Linux (including Chrome OS).
+          ['OS=="mac" or OS=="win" or OS=="linux" or OS=="openbsd" or OS=="freebsd"', {
+            'enable_hidpi%': 1,
+          }],
+
+          # Enable App Launcher on ChromeOS only.
+          ['chromeos==1', {
+            'enable_app_list%': 1,
+          }, {
+            'enable_app_list%': 0,
+          }],
+
+          ['use_aura==1 and OS!="android"', {
+            'use_default_render_theme%': 1,
+          }, {
+            'use_default_render_theme%': 0,
+          }],
+
+          ['use_ozone==1', {
+            'use_ozone_evdev%': 1,
+          }, {
+            'use_ozone_evdev%': 0,
+          }],
+
+          # Set default gomadir.
+          ['OS=="win"', {
+            'gomadir': 'c:\\goma\\goma-win64',
+          }, {
+            'gomadir': '<!(/bin/echo -n ${HOME}/goma)',
+          }],
+
+          # Set the default "target_subarch" on iOS. Valid values are "arm32",
+          # "arm64" and "both" (meaning a fat binary).
+          ['OS=="ios"', {
+            'target_subarch%': 'arm64',
+          }],
+
+          # Set arch variants for MIPS platforms.
+          ['target_arch=="mips64el"', {
+            'conditions': [
+              ['OS=="android"', {
+                'mips_arch_variant%': 'r6',
+              }, {
+                'mips_arch_variant%': 'r2',
+              }],
+            ],
+          }],
+
+          ['target_arch=="mipsel"', {
+            'mips_arch_variant%': 'r1',
+          }],
+
+          # The system root for linux builds.
+          ['OS=="linux" and chromeos==0 and use_sysroot==1', {
+            # sysroot needs to be an absolute path otherwise it generates
+            # incorrect results when passed to pkg-config
+            'conditions': [
+              ['target_arch=="arm"', {
+                'sysroot%': '<!(cd <(DEPTH) && pwd -P)/build/linux/debian_wheezy_arm-sysroot',
+              }],
+              ['target_arch=="arm64"', {
+                'sysroot%': '<!(cd <(DEPTH) && pwd -P)/build/linux/debian_jessie_arm64-sysroot',
+              }],
+              ['target_arch=="x64"', {
+                'sysroot%': '<!(cd <(DEPTH) && pwd -P)/build/linux/debian_wheezy_amd64-sysroot',
+              }],
+              ['target_arch=="ia32"', {
+                'sysroot%': '<!(cd <(DEPTH) && pwd -P)/build/linux/debian_wheezy_i386-sysroot',
+              }],
+              ['target_arch=="mipsel"', {
+                'sysroot%': '<!(cd <(DEPTH) && pwd -P)/build/linux/debian_wheezy_mips-sysroot',
+              }],
+            ],
+          }, {
+            'sysroot%': ''
+          }], # OS=="linux" and use_sysroot==1
+        ],
+      },
+
+      # Copy conditionally-set variables out one scope.
+      'chromeos%': '<(chromeos)',
+      'chromecast%': '<(chromecast)',
+      'is_cast_desktop_build%': '<(is_cast_desktop_build)',
+      'host_arch%': '<(host_arch)',
+      'target_arch%': '<(target_arch)',
+      'target_subarch%': '<(target_subarch)',
+      'mips_arch_variant%': '<(mips_arch_variant)',
+      'mips_dsp_rev%': '<(mips_dsp_rev)',
+      'mips_msa%': '<(mips_msa)',
+      'toolkit_views%': '<(toolkit_views)',
+      'desktop_linux%': '<(desktop_linux)',
+      'use_aura%': '<(use_aura)',
+      'use_ash%': '<(use_ash)',
+      'use_cras%': '<(use_cras)',
+      'use_libpci%': '<(use_libpci)',
+      'use_ozone%': '<(use_ozone)',
+      'use_ozone_evdev%': '<(use_ozone_evdev)',
+      'use_clipboard_aurax11%': '<(use_clipboard_aurax11)',
+      'embedded%': '<(embedded)',
+      'use_openssl_certs%': '<(use_openssl_certs)',
+      'use_external_popup_menu%': '<(use_external_popup_menu)',
+      'enable_viewport%': '<(enable_viewport)',
+      'enable_hidpi%': '<(enable_hidpi)',
+      'enable_wayland_server%': '<(enable_wayland_server)',
+      'enable_wifi_display%': '<(enable_wifi_display)',
+      'android_channel%': '<(android_channel)',
+      'use_goma%': '<(use_goma)',
+      'gomadir%': '<(gomadir)',
+      'enable_app_list%': '<(enable_app_list)',
+      'use_default_render_theme%': '<(use_default_render_theme)',
+      'buildtype%': '<(buildtype)',
+      'branding%': '<(branding)',
+      'branding_path_component%': '<(branding_path_component)',
+      'arm_version%': '<(arm_version)',
+      'sysroot%': '<(sysroot)',
+      'use_sysroot%': '<(use_sysroot)',
+      'chroot_cmd%': '<(chroot_cmd)',
+      'system_libdir%': '<(system_libdir)',
+      'order_profiling%': '<(order_profiling)',
+
+      # TODO(zforman): Remove as soon as no bots depend on this.
+      'dont_embed_build_metadata%': 0,
+
+      # Set to 1 to force Visual C++ to use legacy debug information format /Z7.
+      # This is useful for parallel compilation tools which can't support /Zi.
+      # Only used on Windows.
+      'win_z7%' : 0,
+
+      # Set to 1 to enable dcheck in Release build.
+      'dcheck_always_on%': 0,
+
+      # Set to 1 to make a build that disables unshipped tracing events.
+      # Note: this setting is ignored if buildtype=="Official".
+      'tracing_like_official_build%': 0,
+
+      # Set to 1 to make a build that disables activation of field trial tests
+      # specified in testing/variations/fieldtrial_testing_config_*.json.
+      # Note: this setting is ignored if branding=="Chrome".
+      'fieldtrial_testing_like_official_build%': 0,
+
+      # Disable image loader component extension by default.
+      'image_loader_extension%': 0,
+
+      # Set NEON compilation flags.
+      'arm_neon%': 1,
+
+      # Detect NEON support at run-time. TODO(pasko): This variable is no longer
+      # set to non-zero, remove it when the last official build with NEON
+      # runtime detection propagates to Stable channel.
+      'arm_neon_optional%': 0,
+
+      # Use libjpeg-turbo as the JPEG codec used by Chromium.
+      'use_libjpeg_turbo%': 1,
+
+      # Use system libjpeg. Note that the system's libjepg will be used even if
+      # use_libjpeg_turbo is set.
+      'use_system_libjpeg%': 0,
+
+      # By default, component is set to static_library and it can be overriden
+      # by the GYP command line or by ~/.gyp/include.gypi.
+      'component%': 'static_library',
+
+      # /analyze is off by default on Windows because it is very slow and noisy.
+      # Enable with GYP_DEFINES=win_analyze=1
+      'win_analyze%': 0,
+
+      # /debug:fastlink is off by default on Windows because it generates PDBs
+      # that are machine-local. But, great for local builds.
+      # Enable with GYP_DEFINES=win_fastlink=1
+      'win_fastlink%': 0,
+
+      # Experimental setting to optimize Chrome's DLLs with PGO.
+      'chrome_pgo_phase%': '0',
+
+      # Experimental setting to build the official builds with full WPO.
+      'full_wpo_on_official%': '0',
+
+      # Set to select the Title Case versions of strings in GRD files.
+      'use_titlecase_in_grd%': 0,
+
+      # Remoting compilation is enabled by default. Set to 0 to disable.
+      'remoting%': 1,
+
+      # Configuration policy is enabled by default. Overridden on some
+      # platforms. This can't be disabled manually since code in src/chrome
+      # assumes this is enabled.
+      'configuration_policy': 1,
+
+      # Variable safe_browsing is used to control the build time configuration
+      # for safe browsing feature. Safe browsing can be compiled in 3 different
+      # levels: 0 disables it, 1 enables it fully, and 2 enables mobile
+      # protection via an external API.
+      'safe_browsing%': 1,
+
+      # Web speech is enabled by default. Set to 0 to disable.
+      'enable_web_speech%': 1,
+
+      # 'Ok Google' hotwording is disabled by default. Set to 1 to enable. (This
+      # will download a closed-source NaCl module at startup.) Chrome-branded
+      # ChromeOS builds have this enabled by default.
+      'enable_hotwording%': 0,
+
+      # Notifications are compiled in by default. Set to 0 to disable.
+      'notifications%' : 1,
+
+      # Use dsymutil to generate real .dSYM files on Mac. The default is 0 for
+      # regular builds and 1 for ASan builds.
+      'mac_want_real_dsym%': 'default',
+
+      # If this is set, the clang plugins used on the buildbot will be used.
+      # Run tools/clang/scripts/update.py to make sure they are compiled.
+      # This causes 'clang_chrome_plugins_flags' to be set.
+      # Has no effect if 'clang' is not set as well.
+      'clang_use_chrome_plugins%': 1,
+
+      # Enable building with ASAN (Clang's -fsanitize=address option).
+      # -fsanitize=address only works with clang, but asan=1 implies clang=1
+      # See https://sites.google.com/a/chromium.org/dev/developers/testing/addresssanitizer
+      'asan%': 0,
+      'asan_blacklist%': '<(PRODUCT_DIR)/../../tools/memory/asan/blacklist.txt',
+      # Enable coverage gathering instrumentation in sanitizer tools. This flag
+      # also controls coverage granularity.
+      'sanitizer_coverage%': '',
+      # Enable intra-object-overflow detection in ASan (experimental).
+      'asan_field_padding%': 0,
+
+      # Enable Chromium overrides of the default configurations for various
+      # dynamic tools (like ASan).
+      'use_sanitizer_options%': 0,
+
+      # Enable building with SyzyAsan.
+      # See https://github.com/google/syzygy/wiki/SyzyASanHowTo
+      'syzyasan%': 0,
+
+      # Enable building with LSan (Clang's -fsanitize=leak option).
+      # -fsanitize=leak only works with clang, but lsan=1 implies clang=1
+      # See https://sites.google.com/a/chromium.org/dev/developers/testing/leaksanitizer
+      'lsan%': 0,
+
+      # Enable building with TSan (Clang's -fsanitize=thread option).
+      # -fsanitize=thread only works with clang, but tsan=1 implies clang=1
+      # See http://clang.llvm.org/docs/ThreadSanitizer.html
+      'tsan%': 0,
+      'tsan_blacklist%': '<(PRODUCT_DIR)/../../tools/memory/tsan_v2/ignores.txt',
+
+      # Enable building with MSan (Clang's -fsanitize=memory option).
+      # MemorySanitizer only works with clang, but msan=1 implies clang=1
+      # See http://clang.llvm.org/docs/MemorySanitizer.html
+      'msan%': 0,
+      'msan_blacklist%': '<(PRODUCT_DIR)/../../tools/msan/blacklist.txt',
+      # Track where uninitialized memory originates from. From fastest to
+      # slowest: 0 - no tracking, 1 - track only the initial allocation site, 2
+      # - track the chain of stores leading from allocation site to use site.
+      'msan_track_origins%': 2,
+
+      # Enable building with UBSan (Clang's -fsanitize=undefined option).
+      # -fsanitize=undefined only works with clang, but ubsan=1 implies clang=1
+      # See http://clang.llvm.org/docs/UsersManual.html
+      'ubsan%': 0,
+      'ubsan_blacklist%': '<(PRODUCT_DIR)/../../tools/ubsan/blacklist.txt',
+      'ubsan_security_blacklist%': '<(PRODUCT_DIR)/../../tools/ubsan/security_blacklist.txt',
+      'ubsan_vptr_blacklist%': '<(PRODUCT_DIR)/../../tools/ubsan/vptr_blacklist.txt',
+
+      # Enable building with UBsan's vptr (Clang's -fsanitize=vptr option).
+      # -fsanitize=vptr only works with clang, but ubsan_vptr=1 implies clang=1
+      # ubsan_security also enables UBSan's vptr.
+      'ubsan_security%': 0,
+      'ubsan_vptr%': 0,
+
+      # Use dynamic libraries instrumented by one of the sanitizers
+      # instead of the standard system libraries. Set this flag to build the
+      # libraries from source.
+      'use_instrumented_libraries%': 0,
+
+      # Use dynamic libraries instrumented by one of the sanitizers
+      # instead of the standard system libraries. Set this flag to download
+      # prebuilt binaries from GCS.
+      'use_prebuilt_instrumented_libraries%': 0,
+
+      # Use libc++ (third_party/libc++ and third_party/libc++abi) instead of
+      # stdlibc++ as standard library. This is intended to use for instrumented
+      # builds.
+      'use_custom_libcxx%': 0,
+
+      # Use the provided profiled order file to link Chrome image with it.
+      # This makes Chrome faster by better using CPU cache when executing code.
+      # This is known as PGO (profile guided optimization).
+      # See https://sites.google.com/a/google.com/chrome-msk/dev/boot-speed-up-effort
+      'order_text_section%' : "",
+
+      # Set to 1 compile with -fPIC cflag on linux. This is a must for shared
+      # libraries on linux x86-64 and arm, plus ASLR.
+      'linux_fpic%': 1,
+
+      # Whether one-click signin is enabled or not.
+      'enable_one_click_signin%': 0,
+
+      # Enable Chrome browser extensions
+      'enable_extensions%': 1,
+
+      # Enable basic printing support and UI.
+      'enable_basic_printing%': 1,
+
+      # Enable printing with print preview. It does not imply
+      # enable_basic_printing. It's possible to build Chrome with preview only.
+      'enable_print_preview%': 1,
+
+      # For CLD2, the size of the tables that should be included in the build
+      # See third_party/cld_2/cld_2.gyp for more information.
+      #   0: Small tables, high accuracy
+      #   2: Large tables, higher accuracy
+      'cld2_table_size%': 2,
+
+      # Enable spell checker.
+      'enable_spellcheck%': 1,
+
+      # Use the operating system spellchecker, e.g. NSSpellChecker on Mac or
+      # SpellCheckerSession on Android.
+      'use_browser_spellchecker%': 0,
+
+      # Use Minikin hyphenation engine.
+      'use_minikin_hyphenation%': 0,
+
+      # Webrtc compilation is enabled by default. Set to 0 to disable.
+      'enable_webrtc%': 1,
+
+      # Media router support is enabled by default. Set to 0 to disable.
+      'enable_media_router%': 1,
+
+      # Enables use of the session service, which is enabled by default.
+      # Support for disabling depends on the platform.
+      'enable_session_service%': 1,
+
+      # Enables theme support, which is enabled by default.  Support for
+      # disabling depends on the platform.
+      'enable_themes%': 1,
+
+      # Enable the task manager by default.
+      'enable_task_manager%': 1,
+
+      # Enables used resource whitelist generation; disabled by default.
+      'enable_resource_whitelist_generation%': 0,
+
+      # Enable FILE support by default.
+      'disable_file_support%': 0,
+
+      # Enable FTP support by default.
+      'disable_ftp_support%': 0,
+
+      # Do not use the platform ICU alternatives by default.
+      'use_platform_icu_alternatives%': 0,
+
+      # Do not disable brotli filter by default.
+      'disable_brotli_filter%': 0,
+
+      # Use of precompiled headers on Windows.
+      #
+      # This variable may be explicitly set to 1 (enabled) or 0
+      # (disabled) in ~/.gyp/include.gypi or via the GYP command line.
+      # This setting will override the default.
+      #
+      # See
+      # https://chromium.googlesource.com/chromium/src/+/master/docs/windows_precompiled_headers.md
+      # for details.
+      'chromium_win_pch%': 0,
+
+      # Clang stuff.
+      'make_clang_dir%': 'third_party/llvm-build/Release+Asserts',
+      # Set this to true when building with Clang.
+      # See https://chromium.googlesource.com/chromium/src/+/master/docs/clang.md for details.
+      # If this is set, clang is used as both host and target compiler in
+      # cross-compile builds.
+      'clang%': 0,
+
+      # Use experimental lld linker instead of the platform's default linker.
+      'use_lld%': 0,
+
+      # Enable plugin installation by default.
+      'enable_plugin_installation%': 1,
+
+      # Specifies whether to use canvas_skia.cc in place of platform
+      # specific implementations of gfx::Canvas. Affects text drawing in the
+      # Chrome UI.
+      # TODO(asvitkine): Enable this on all platforms and delete this flag.
+      #                  http://crbug.com/105550
+      'use_canvas_skia%': 0,
+
+      # Set to "drmemory" to configure the build to work with DrMemory.
+      'build_for_tool%': '',
+
+      'wix_path%': '<(DEPTH)/third_party/wix',
+
+      # Supervised users are enabled by default.
+      'enable_supervised_users%': 1,
+
+      'enable_mdns%' : 0,
+      'enable_service_discovery%': 0,
+      'enable_hangout_services_extension%': 0,
+
+       # Enable the Syzygy optimization step.
+      'syzygy_optimize%': 0,
+
+      # Enable hole punching for the protected video.
+      'video_hole%': 0,
+
+      # Automatically select platforms under ozone. Turn this off to
+      # build only explicitly selected platforms.
+      'ozone_auto_platforms%': 1,
+
+      # Disable the display for a chromecast build. Set to 1 perform an audio-
+      # only build.
+      'disable_display%': 0,
+
+      # If this is set clang is used as host compiler, but not as target
+      # compiler. Always do this by default.
+      'host_clang%': 1,
+
+      # Variables to control Link-Time Optimization (LTO).
+      # On Android, when using GCC LTO, the variable use_lto enables LTO on code
+      # compiled with -Os, and use_lto_o2 enables LTO on code compiled with -O2.
+      # On other platforms (including Android with Clang), use_lto enables LTO
+      # in all translation units, and use_lto_o2 has no effect.
+      #
+      # On Linux and Android, when using LLVM LTO, the script
+      # build/download_gold_plugin.py must be run to download a linker plugin.
+      # On Mac, LLVM needs to be built from scratch using
+      # tools/clang/scripts/update.py and the absolute path to
+      # third_party/llvm-build/Release+Asserts/lib must be added to
+      # $DYLD_LIBRARY_PATH to pick up the right version of the linker plugin.
+      # TODO(pcc): Teach build system to use -lto_library flag to specify path
+      # to linker plugin on Mac.
+      #
+      # On Android/GCC, the variables must *not* be enabled at the same time.
+      # In this case LTO would 'merge' the optimization flags at link-time
+      # which would lead to all code be optimized with -O2. See crbug.com/407544
+      'use_lto%': 0,
+      'use_lto_o2%': 0,
+
+      # Allowed level of identical code folding in the gold linker.
+      'gold_icf_level%': 'all',
+
+      # Libxkbcommon usage.
+      'use_xkbcommon%': 0,
+
+      # Whether we use GTKv3 on linux.
+      'use_gtk3%': 0,
+
+      # Control Flow Integrity for virtual calls and casts.
+      # See http://clang.llvm.org/docs/ControlFlowIntegrity.html
+      'cfi_vptr%': 0,
+      # TODO(krasin): remove it. See https://crbug.com/626794.
+      'cfi_cast%': 0,
+      'cfi_diag%': 0,
+
+      'cfi_blacklist%': '<(PRODUCT_DIR)/../../tools/cfi/blacklist.txt',
+
+      # Whether the entire browser uses toolkit-views on Mac instead of Cocoa.
+      'mac_views_browser%': 0,
+
+      # By default, use ICU data file (icudtl.dat).
+      'icu_use_data_file_flag%': 1,
+
+      # Turn on JNI generation optimizations by default.
+      'optimize_jni_generation%': 1,
+
+      'conditions': [
+        # A flag for POSIX platforms
+        ['OS=="win"', {
+          'os_posix%': 0,
+        }, {
+          'os_posix%': 1,
+        }],
+
+        # A flag for BSD platforms
+        ['OS=="freebsd" or OS=="openbsd"', {
+          'os_bsd%': 1,
+        }, {
+          'os_bsd%': 0,
+        }],
+
+        # NSS usage.
+        ['(OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris")', {
+          'use_nss_certs%': 1,
+        }, {
+          'use_nss_certs%': 0,
+        }],
+
+        # libudev usage.  This currently only affects the content layer.
+        ['OS=="linux" and embedded==0', {
+          'use_udev%': 1,
+        }, {
+          'use_udev%': 0,
+        }],
+
+        # Flags to use X11 on non-Mac POSIX platforms.
+        ['OS=="win" or OS=="mac" or OS=="ios" or OS=="android" or use_ozone==1', {
+          'use_x11%': 0,
+        }, {
+          'use_x11%': 1,
+        }],
+
+        # Flags to use glib.
+        ['OS=="win" or OS=="mac" or OS=="ios" or OS=="android" or use_ozone==1', {
+          'use_glib%': 0,
+        }, {
+          'use_glib%': 1,
+        }],
+
+        # Flags to use Wayland server support.
+        ['chromeos==1', {
+          'enable_wayland_server%': 1,
+        }, {
+          'enable_wayland_server%': 0,
+        }],
+
+        # Flags to use pango and cairo.
+        ['OS=="win" or OS=="mac" or OS=="ios" or OS=="android" or embedded==1', {
+          'use_pango%': 0,
+          'use_cairo%': 0,
+        }, {
+          'use_pango%': 1,
+          'use_cairo%': 1,
+        }],
+
+        # DBus usage.
+        ['(OS=="linux" or OS=="openbsd" or OS=="freebsd") and embedded==0', {
+          'use_dbus%': 1,
+        }, {
+          'use_dbus%': 0,
+        }],
+
+        # We always use skia text rendering in Aura on Windows, since GDI
+        # doesn't agree with our BackingStore.
+        # TODO(beng): remove once skia text rendering is on by default.
+        ['use_aura==1 and OS=="win"', {
+          'enable_skia_text%': 1,
+        }],
+
+        # A flag to enable or disable our compile-time dependency
+        # on gnome-keyring. If that dependency is disabled, no gnome-keyring
+        # support will be available. This option is useful
+        # for Linux distributions and for Aura.
+        ['OS!="linux" or chromeos==1', {
+          'use_gnome_keyring%': 0,
+        }, {
+          'use_gnome_keyring%': 1,
+        }],
+
+        ['OS=="mac" or OS=="ios"', {
+          # Mac and iOS want Title Case strings
+          'use_titlecase_in_grd%': 1,
+        }],
+
+        # Enable loader extensions on Chrome OS.
+        ['chromeos==1', {
+          'image_loader_extension%': 1,
+        }, {
+          'image_loader_extension%': 0,
+        }],
+
+        ['OS=="win" or OS=="mac" or (OS=="linux" and chromeos==0)', {
+          'enable_one_click_signin%': 1,
+        }],
+
+        ['OS=="android"', {
+          'enable_extensions%': 0,
+          'cld2_table_size%': 0,
+          'enable_themes%': 0,
+          'remoting%': 0,
+          'enable_basic_printing%': 1,
+          'enable_print_preview%': 0,
+          'enable_task_manager%':0,
+          'video_hole%': 1,
+        }],
+
+        # Android and OSX have built-in spellcheckers that can be utilized.
+        ['OS=="android" or OS=="mac"', {
+          'use_browser_spellchecker%': 1,
+        }],
+
+        # Android has hyphenation dictionaries for Minikin to use.
+        ['OS=="android"', {
+          'use_minikin_hyphenation%': 1,
+        }],
+
+        # Enables proprietary codecs and demuxers; e.g. H264, AAC, MP3, and MP4.
+        # We always build Google Chrome and Chromecast with proprietary codecs.
+        ['branding=="Chrome" or chromecast==1', {
+          'proprietary_codecs%': 1,
+        }, {
+          'proprietary_codecs%': 0,
+        }],
+
+        # Enable Link Time Optimization for the official Linux Chrome.
+        # This requires LLVM Gold plugin to be downloaded.
+        # See src/tools/clang/scripts/update.py
+        ['OS=="linux" and target_arch=="x64" and buildtype=="Official" and branding=="Chrome" and chromeos==0', {
+           'use_lto%': 1,
+        }],
+
+        # Enable hotwording on Chrome-branded ChromeOS builds.
+        ['branding=="Chrome" and chromeos==1', {
+          'enable_hotwording%': 1,
+        }],
+
+        ['OS=="android"', {
+          'enable_webrtc%': 1,
+        }],
+
+        ['OS=="ios"', {
+          'configuration_policy': 0,
+          'disable_ftp_support%': 1,
+          'enable_extensions%': 0,
+          'cld2_table_size%': 0,
+          'enable_basic_printing%': 0,
+          'enable_print_preview%': 0,
+          'enable_session_service%': 0,
+          'enable_spellcheck%': 0,
+          'enable_themes%': 0,
+          'enable_webrtc%': 0,
+          'notifications%': 0,
+          'remoting%': 0,
+          'safe_browsing%': 2,
+          'enable_supervised_users%': 0,
+          'enable_task_manager%': 0,
+          'enable_media_router%': 0,
+        }],
+
+        # Use GPU accelerated cross process image transport by default
+        # on linux and *BSD builds with the Aura window manager
+        ['use_aura==1 and (OS=="linux" or OS=="openbsd" or OS=="freebsd")', {
+          'ui_compositor_image_transport%': 1,
+        }, {
+          'ui_compositor_image_transport%': 0,
+        }],
+
+        # Turn precompiled headers on by default.
+        ['OS=="win" and buildtype!="Official"', {
+          'chromium_win_pch%': 1
+        }],
+
+        # Whether PDF plugin is enabled, and which options it supports.
+        ['OS=="android" or OS=="ios" or (embedded==1 and chromecast==0)', {
+          'enable_pdf%': 0,
+          'pdf_enable_v8%': 0,
+        }, {
+          'enable_pdf%': 1,
+          'pdf_enable_v8%': 1,
+        }],
+        ['OS=="android" or OS=="ios" or (embedded==1 and chromecast==0)', {
+          'pdf_enable_xfa%': 0,
+        }, {
+          'pdf_enable_xfa%': 0,
+        }],
+
+        ['chromeos==1 or OS=="android" or OS=="ios" or desktop_linux==1', {
+          'enable_plugin_installation%': 0,
+        }, {
+          'enable_plugin_installation%': 1,
+        }],
+
+        # Whether PPAPI is enabled.
+        ['OS=="android" or OS=="ios" or (embedded==1 and chromecast==0)', {
+          'enable_plugins%': 0,
+        }, {
+          'enable_plugins%': 1,
+        }],
+
+        # linux_use_bundled_gold: whether to use the gold linker binary checked
+        # into third_party/binutils.  Force this off via GYP_DEFINES when you
+        # are using a custom toolchain and need to control -B in ldflags.
+        # Do not use 32-bit gold on 32-bit hosts as it runs out address space
+        # for component=static_library builds.
+        ['((OS=="linux" or OS=="android") and (target_arch=="x64" or target_arch=="arm" or (target_arch=="ia32" and host_arch=="x64"))) or (OS=="linux" and target_arch=="mipsel")', {
+          'linux_use_bundled_gold%': 1,
+        }, {
+          'linux_use_bundled_gold%': 0,
+        }],
+
+        # linux_use_bundled_binutils: whether to use the binary binutils
+        # checked into third_party/binutils.  These are not multi-arch so cannot
+        # be used except on x86 and x86-64 (the only two architectures which
+        # are currently checke in).  Force this off via GYP_DEFINES when you
+        # are using a custom toolchain and need to control -B in cflags.
+        ['OS=="linux" and (target_arch=="x64")', {
+          'linux_use_bundled_binutils%': 1,
+        }, {
+          'linux_use_bundled_binutils%': 0,
+        }],
+
+        # linux_use_gold_flags: whether to use build flags that rely on gold.
+        # On by default for x64 Linux.
+        ['OS=="linux" and target_arch=="x64"', {
+          'linux_use_gold_flags%': 1,
+        }, {
+          'linux_use_gold_flags%': 0,
+        }],
+
+        # linux_use_debug_fission: whether to use split DWARF debug info
+        # files. This can reduce link time significantly, but is incompatible
+        # with some utilities such as icecc and ccache. Requires gold and
+        # gcc >= 4.8 or clang.
+        # http://gcc.gnu.org/wiki/DebugFission
+        ['OS=="linux" and target_arch=="x64"', {
+          'linux_use_debug_fission%': 1,
+        }, {
+          'linux_use_debug_fission%': 0,
+        }],
+
+        ['OS=="android" or OS=="ios"', {
+          'enable_captive_portal_detection%': 0,
+        }, {
+          'enable_captive_portal_detection%': 1,
+        }],
+
+        # Enable Skia UI text drawing incrementally on different platforms.
+        # http://crbug.com/105550
+        #
+        # On Aura, this allows per-tile painting to be used in the browser
+        # compositor.
+        ['OS!="android" and OS!="ios"', {
+          'use_canvas_skia%': 1,
+        }],
+
+        ['chromeos==1', {
+          'enable_basic_printing%': 1,
+          'enable_print_preview%': 1,
+        }],
+
+        # Whether tests targets should be run, archived or just have the
+        # dependencies verified. All the tests targets have the '_run' suffix,
+        # e.g. base_unittests_run runs the target base_unittests. The test
+        # target always calls tools/swarming_client/isolate.py. See the script's
+        # --help for more information. Meant to be overriden with GYP_DEFINES.
+        # TODO(maruel): Remove the conditions as more configurations are
+        # supported.
+        ['OS!="ios" and OS!="android" and chromeos==0 and OS!="openbsd" and OS!="freebsd"', {
+          'test_isolation_mode%': 'check',
+        }, {
+          'test_isolation_mode%': 'noop',
+        }],
+        # Whether Android build uses OpenMAX DL FFT.
+        ['OS=="android" and ((target_arch=="arm" and arm_version >= 7) or target_arch=="ia32" or target_arch=="x64" or target_arch=="arm64" or target_arch=="mipsel")', {
+          # Currently only supported on Android ARMv7+, ARM64, ia32, x64 and mipsel.
+          # When enabled, this will also enable WebAudio support on
+          # Android for these architectures.  Default is enabled.  Whether
+          # WebAudio is actually available depends on runtime settings
+          # and flags.
+          'use_openmax_dl_fft%': 1,
+        }, {
+          'use_openmax_dl_fft%': 0,
+        }],
+        ['OS=="win" or OS=="linux" or OS=="openbsd" or OS=="freebsd"', {
+          'enable_mdns%' : 1,
+        }],
+
+        # Disable various features by default on embedded.
+        ['embedded==1', {
+          'remoting%': 0,
+          'enable_basic_printing%': 0,
+          'enable_print_preview%': 0,
+        }],
+
+        ['sysroot!=""', {
+          'pkg-config': '<(chroot_cmd) <(DEPTH)/build/linux/pkg-config-wrapper "<(sysroot)" "<(target_arch)" "<(system_libdir)"',
+        }, {
+          'pkg-config': 'pkg-config'
+        }],
+
+        # Enable WebVR support by default on Android
+        # Still requires command line flag to access API
+        ['OS=="android"', {
+          'enable_webvr%': 1,
+        }, {
+          'enable_webvr%': 0,
+        }],
+
+        ['order_profiling==0', {
+          # Set to 1 to enable fast builds. Set to 2 for even faster builds
+          # (it disables debug info for fastest compilation - only for use
+          # on compile-only bots).
+          'fastbuild%': 0,
+        }, {
+          # With instrumentation enabled, debug info puts libchrome.so over 4gb,
+          # which causes the linker to produce an invalid ELF.
+          # http://crbug.com/574476
+          'fastbuild%': 2,
+        }],
+      ],
+
+      # Kasko reporting is disabled by default, but may get enabled below.
+      'kasko%': 0,
+
+      # Setting this to '0' will cause V8's startup snapshot to be
+      # embedded in the binary instead of being a external files.
+      'v8_use_external_startup_data%': 1,
+
+      # Set this to 1 to enable use of concatenated impulse responses
+      # for the HRTF panner in WebAudio.
+      'use_concatenated_impulse_responses': 1,
+
+      # You can set the variable 'use_official_google_api_keys' to 1
+      # to use the Google-internal file containing official API keys
+      # for Google Chrome even in a developer build.  Setting this
+      # variable explicitly to 1 will cause your build to fail if the
+      # internal file is missing.
+      #
+      # The variable is documented here, but not handled in this file;
+      # see //google_apis/determine_use_official_keys.gypi for the
+      # implementation.
+      #
+      # Set the variable to 0 to not use the internal file, even when
+      # it exists in your checkout.
+      #
+      # Leave it unset in your include.gypi to have the variable
+      # implicitly set to 1 if you have
+      # src/google_apis/internal/google_chrome_api_keys.h in your
+      # checkout, and implicitly set to 0 if not.
+      #
+      # Note that official builds always behave as if the variable
+      # was explicitly set to 1, i.e. they always use official keys,
+      # and will fail to build if the internal file is missing.
+      #
+      # NOTE: You MUST NOT explicitly set the variable to 2 in your
+      # include.gypi or by other means. Due to subtleties of GYP, this
+      # is not the same as leaving the variable unset, even though its
+      # default value in
+      # //google_apis/determine_use_official_keys.gypi is 2.
+
+      # Set these to bake the specified API keys and OAuth client
+      # IDs/secrets into your build.
+      #
+      # If you create a build without values baked in, you can instead
+      # set environment variables to provide the keys at runtime (see
+      # src/google_apis/google_api_keys.h for details).  Features that
+      # require server-side APIs may fail to work if no keys are
+      # provided.
+      #
+      # Note that if you are building an official build or if
+      # use_official_google_api_keys has been set to 1 (explicitly or
+      # implicitly), these values will be ignored and the official
+      # keys will be used instead.
+      'google_api_key%': '',
+      'google_default_client_id%': '',
+      'google_default_client_secret%': '',
+      # Native Client is enabled by default.
+      'disable_nacl%': '0',
+
+      # Native Client toolchains, enabled by default.
+      'disable_pnacl%': 0,
+      'disable_newlib%': 0,
+
+      # Sets the default version name and code for Android app, by default we
+      # do a developer build.
+      'android_app_version_name%': 'Developer Build',
+      'android_app_version_code%': 1,
+
+      # Use the internal version of the framework to build Android WebView.
+      'use_webview_internal_framework%': 0,
+    },
+
+    # Copy conditionally-set variables out one scope.
+    'branding%': '<(branding)',
+    'branding_path_component%': '<(branding_path_component)',
+    'buildtype%': '<(buildtype)',
+    'target_arch%': '<(target_arch)',
+    'target_subarch%': '<(target_subarch)',
+    'mips_arch_variant%': '<(mips_arch_variant)',
+    'mips_dsp_rev%': '<(mips_dsp_rev)',
+    'mips_msa%': '<(mips_msa)',
+    'host_arch%': '<(host_arch)',
+    'toolkit_views%': '<(toolkit_views)',
+    'ui_compositor_image_transport%': '<(ui_compositor_image_transport)',
+    'use_aura%': '<(use_aura)',
+    'use_ash%': '<(use_ash)',
+    'use_cras%': '<(use_cras)',
+    'use_libpci%': '<(use_libpci)',
+    'use_openssl_certs%': '<(use_openssl_certs)',
+    'use_external_popup_menu%': '<(use_external_popup_menu)',
+    'use_nss_certs%': '<(use_nss_certs)',
+    'use_udev%': '<(use_udev)',
+    'os_bsd%': '<(os_bsd)',
+    'os_posix%': '<(os_posix)',
+    'use_dbus%': '<(use_dbus)',
+    'use_glib%': '<(use_glib)',
+    'use_pango%': '<(use_pango)',
+    'use_cairo%': '<(use_cairo)',
+    'use_ozone%': '<(use_ozone)',
+    'use_ozone_evdev%': '<(use_ozone_evdev)',
+    'use_xkbcommon%': '<(use_xkbcommon)',
+    'use_gtk3%': '<(use_gtk3)',
+    'use_clipboard_aurax11%': '<(use_clipboard_aurax11)',
+    'desktop_linux%': '<(desktop_linux)',
+    'use_x11%': '<(use_x11)',
+    'use_gnome_keyring%': '<(use_gnome_keyring)',
+    'linux_fpic%': '<(linux_fpic)',
+    'chromeos%': '<(chromeos)',
+    'chromecast%': '<(chromecast)',
+    'is_cast_desktop_build%': '<(is_cast_desktop_build)',
+    'enable_viewport%': '<(enable_viewport)',
+    'enable_hidpi%': '<(enable_hidpi)',
+    'enable_wayland_server%': '<(enable_wayland_server)',
+    'enable_wifi_display%': '<(enable_wifi_display)',
+    'image_loader_extension%': '<(image_loader_extension)',
+    'fastbuild%': '<(fastbuild)',
+    'win_z7%': '<(win_z7)',
+    'dcheck_always_on%': '<(dcheck_always_on)',
+    'tracing_like_official_build%': '<(tracing_like_official_build)',
+    'fieldtrial_testing_like_official_build%': '<(fieldtrial_testing_like_official_build)',
+    'arm_version%': '<(arm_version)',
+    'arm_neon%': '<(arm_neon)',
+    'arm_neon_optional%': '<(arm_neon_optional)',
+    'sysroot%': '<(sysroot)',
+    'use_sysroot%': '<(use_sysroot)',
+    'pkg-config%': '<(pkg-config)',
+    'chroot_cmd%': '<(chroot_cmd)',
+    'system_libdir%': '<(system_libdir)',
+    'component%': '<(component)',
+    'win_analyze%': '<(win_analyze)',
+    'win_fastlink%': '<(win_fastlink)',
+    'chrome_pgo_phase%': '<(chrome_pgo_phase)',
+    'full_wpo_on_official%': '<(full_wpo_on_official)',
+    'enable_resource_whitelist_generation%': '<(enable_resource_whitelist_generation)',
+    'use_titlecase_in_grd%': '<(use_titlecase_in_grd)',
+    'remoting%': '<(remoting)',
+    'enable_one_click_signin%': '<(enable_one_click_signin)',
+    'enable_media_router%': '<(enable_media_router)',
+    'enable_webrtc%': '<(enable_webrtc)',
+    'chromium_win_pch%': '<(chromium_win_pch)',
+    'configuration_policy': '<(configuration_policy)',
+    'safe_browsing%': '<(safe_browsing)',
+    'enable_web_speech%': '<(enable_web_speech)',
+    'enable_hotwording%': '<(enable_hotwording)',
+    'notifications%': '<(notifications)',
+    'clang_use_chrome_plugins%': '<(clang_use_chrome_plugins)',
+    'mac_want_real_dsym%': '<(mac_want_real_dsym)',
+    'asan%': '<(asan)',
+    'asan_blacklist%': '<(asan_blacklist)',
+    'sanitizer_coverage%': '<(sanitizer_coverage)',
+    'asan_field_padding%': '<(asan_field_padding)',
+    'use_sanitizer_options%': '<(use_sanitizer_options)',
+    'syzyasan%': '<(syzyasan)',
+    'kasko%': '<(kasko)',
+    'syzygy_optimize%': '<(syzygy_optimize)',
+    'lsan%': '<(lsan)',
+    'msan%': '<(msan)',
+    'msan_blacklist%': '<(msan_blacklist)',
+    'msan_track_origins%': '<(msan_track_origins)',
+    'tsan%': '<(tsan)',
+    'tsan_blacklist%': '<(tsan_blacklist)',
+    'ubsan%': '<(ubsan)',
+    'ubsan_blacklist%': '<(ubsan_blacklist)',
+    'ubsan_security%': '<(ubsan_security)',
+    'ubsan_security_blacklist%': '<(ubsan_security_blacklist)',
+    'ubsan_vptr%': '<(ubsan_vptr)',
+    'ubsan_vptr_blacklist%': '<(ubsan_vptr_blacklist)',
+    'use_instrumented_libraries%': '<(use_instrumented_libraries)',
+    'use_prebuilt_instrumented_libraries%': '<(use_prebuilt_instrumented_libraries)',
+    'use_custom_libcxx%': '<(use_custom_libcxx)',
+    'order_profiling%': '<(order_profiling)',
+    'order_text_section%': '<(order_text_section)',
+    'enable_extensions%': '<(enable_extensions)',
+    'enable_pdf%': '<(enable_pdf)',
+    'pdf_enable_v8%': '<(pdf_enable_v8)',
+    'pdf_enable_xfa%': '<(pdf_enable_xfa)',
+    'enable_plugin_installation%': '<(enable_plugin_installation)',
+    'enable_plugins%': '<(enable_plugins)',
+    'enable_session_service%': '<(enable_session_service)',
+    'enable_themes%': '<(enable_themes)',
+    'linux_use_bundled_gold%': '<(linux_use_bundled_gold)',
+    'linux_use_bundled_binutils%': '<(linux_use_bundled_binutils)',
+    'linux_use_gold_flags%': '<(linux_use_gold_flags)',
+    'linux_use_debug_fission%': '<(linux_use_debug_fission)',
+    'use_canvas_skia%': '<(use_canvas_skia)',
+    'test_isolation_mode%': '<(test_isolation_mode)',
+    'enable_basic_printing%': '<(enable_basic_printing)',
+    'enable_print_preview%': '<(enable_print_preview)',
+    'enable_spellcheck%': '<(enable_spellcheck)',
+    'use_browser_spellchecker%': '<(use_browser_spellchecker)',
+    'use_minikin_hyphenation%': '<(use_minikin_hyphenation)',
+    'cld2_table_size%': '<(cld2_table_size)',
+    'enable_captive_portal_detection%': '<(enable_captive_portal_detection)',
+    'disable_file_support%': '<(disable_file_support)',
+    'disable_ftp_support%': '<(disable_ftp_support)',
+    'use_platform_icu_alternatives%': '<(use_platform_icu_alternatives)',
+    'disable_brotli_filter%': '<(disable_brotli_filter)',
+    'enable_task_manager%': '<(enable_task_manager)',
+    'wix_path%': '<(wix_path)',
+    'use_libjpeg_turbo%': '<(use_libjpeg_turbo)',
+    'use_system_libjpeg%': '<(use_system_libjpeg)',
+    'android_channel%': '<(android_channel)',
+    'icu_use_data_file_flag%': '<(icu_use_data_file_flag)',
+    'gyp_managed_install%': 0,
+    'create_standalone_apk%': 1,
+    'enable_app_list%': '<(enable_app_list)',
+    'use_default_render_theme%': '<(use_default_render_theme)',
+    'google_api_key%': '<(google_api_key)',
+    'google_default_client_id%': '<(google_default_client_id)',
+    'google_default_client_secret%': '<(google_default_client_secret)',
+    'enable_supervised_users%': '<(enable_supervised_users)',
+    'enable_mdns%' : '<(enable_mdns)',
+    'enable_service_discovery%' : '<(enable_service_discovery)',
+    'enable_hangout_services_extension%' : '<(enable_hangout_services_extension)',
+    'proprietary_codecs%': '<(proprietary_codecs)',
+    'use_goma%': '<(use_goma)',
+    'gomadir%': '<(gomadir)',
+    'use_lto%': '<(use_lto)',
+    'use_lto_o2%': '<(use_lto_o2)',
+    'gold_icf_level%': '<(gold_icf_level)',
+    'video_hole%': '<(video_hole)',
+    'v8_use_external_startup_data%': '<(v8_use_external_startup_data)',
+    'cfi_vptr%': '<(cfi_vptr)',
+    'cfi_cast%': '<(cfi_cast)',
+    'cfi_diag%': '<(cfi_diag)',
+    'cfi_blacklist%': '<(cfi_blacklist)',
+    'mac_views_browser%': '<(mac_views_browser)',
+    'android_app_version_name%': '<(android_app_version_name)',
+    'android_app_version_code%': '<(android_app_version_code)',
+    'use_webview_internal_framework%': '<(use_webview_internal_framework)',
+    'enable_webvr%': '<(enable_webvr)',
+
+    # Turns on compiler optimizations in V8 in Debug build.
+    'v8_optimized_debug%': 1,
+
+    # Use system protobuf instead of bundled one.
+    'use_system_protobuf%': 0,
+
+    # Use system yasm instead of bundled one.
+    'use_system_yasm%': 0,
+
+    # Use system ICU instead of bundled one.
+    'use_system_icu%' : 0,
+
+    # Default to enabled PIE; this is important for ASLR but we may need to be
+    # able to turn it off for various reasons.
+    'linux_disable_pie%': 0,
+
+    # The release channel that this build targets. This is used to restrict
+    # channel-specific build options, like which installer packages to create.
+    # The default is 'all', which does no channel-specific filtering.
+    'channel%': 'all',
+
+    # Override chromium_mac_pch and set it to 0 to suppress the use of
+    # precompiled headers on the Mac.  Prefix header injection may still be
+    # used, but prefix headers will not be precompiled.  This is useful when
+    # using distcc to distribute a build to compile slaves that don't
+    # share the same compiler executable as the system driving the compilation,
+    # because precompiled headers rely on pointers into a specific compiler
+    # executable's image.  Setting this to 0 is needed to use an experimental
+    # Linux-Mac cross compiler distcc farm.
+    'chromium_mac_pch%': 1,
+
+    # The default value for mac_strip in target_defaults. This cannot be
+    # set there, per the comment about variable% in a target_defaults.
+    'mac_strip_release%': 0,
+
+    # Set to 1 to enable java code coverage. Instruments classes during build
+    # to produce .ec files during runtime.
+    'emma_coverage%': 0,
+
+    # EMMA filter string consisting of a list of inclusion/exclusion patterns
+    # separated with whitespace and/or comma. Only has effect if
+    # 'emma_coverage=1'.
+    'emma_filter%': '',
+
+    # Set to 1 to enable running Android lint on java/class files.
+    'android_lint%': 1,
+
+    # Although base/allocator lets you select a heap library via an
+    # environment variable, the shim it uses sometimes gets in the way.
+    # To disable it entirely, and switch to normal msvcrt, do e.g.
+    #  'win_use_allocator_shim': 0,
+    #  'win_release_RuntimeLibrary': 2
+    # to ~/.gyp/include.gypi, gclient runhooks --force, and do a release build.
+    'win_use_allocator_shim%': 1, # 1 = shim allocator; 0 = msvcrt
+
+    # Enables the unified allocator shim (experimental) which routes all the
+    # alloc calls to base/. Right now is supported on Linux Desktop only.
+    # http://crbug.com/550886 .
+    'use_experimental_allocator_shim%': 0,
+
+    # TODO(bradnelson): eliminate this when possible.
+    # To allow local gyp files to prevent release.vsprops from being included.
+    # Yes(1) means include release.vsprops.
+    # Once all vsprops settings are migrated into gyp, this can go away.
+    'msvs_use_common_release%': 1,
+
+    # TODO(bradnelson): eliminate this when possible.
+    # To allow local gyp files to override additional linker options for msvs.
+    # Yes(1) means set use the common linker options.
+    'msvs_use_common_linker_extras%': 1,
+
+    # TODO(sgk): eliminate this if possible.
+    # It would be nicer to support this via a setting in 'target_defaults'
+    # in chrome/app/locales/locales.gypi overriding the setting in the
+    # 'Debug' configuration in the 'target_defaults' dict below,
+    # but that doesn't work as we'd like.
+    'msvs_debug_link_incremental%': '2',
+
+    # Needed for some of the largest modules.
+    'msvs_debug_link_nonincremental%': '1',
+
+    # Turns on Use Library Dependency Inputs for linking chrome.dll on Windows
+    # to get incremental linking to be faster in debug builds.
+    'incremental_chrome_dll%': '0',
+
+    # Experimental setting to break chrome.dll into multiple pieces based on
+    # process type.
+    'chrome_multiple_dll%': '0',
+
+    # Whether the VS xtree header has been patched to disable warning 4702. If
+    # it has, then we don't need to disable 4702 (unreachable code warning).
+    # The patch is preapplied to the internal toolchain and hence all bots.
+    'msvs_xtree_patched%': '<!pymod_do_main(win_is_xtree_patched)',
+
+    # Clang stuff.
+    'clang%': '<(clang)',
+    'host_clang%': '<(host_clang)',
+    'make_clang_dir%': '<(make_clang_dir)',
+    'use_lld%': '<(use_lld)',
+
+    # Control which version of clang to use when building for iOS.  If set to
+    # '1', uses the version of clang that ships with Xcode.  If set to '0', uses
+    # the version of clang that ships with the Chromium source.  This variable
+    # is automatically set to '1' in Official builds.
+    'clang_xcode%': 0,
+
+    # These two variables can be set in GYP_DEFINES while running
+    # |gclient runhooks| to let clang run a plugin in every compilation.
+    # Only has an effect if 'clang=1' is in GYP_DEFINES as well.
+    # Example:
+    #     GYP_DEFINES='clang=1 clang_load=/abs/path/to/libPrintFunctionNames.dylib clang_add_plugin=print-fns' gclient runhooks
+
+    'clang_load%': '',
+    'clang_add_plugin%': '',
+
+    # Tell ld64 to write map files describing binary layout. Useful
+    # for looking at what contributes to binary size, e.g. with
+    # https://github.com/nico/bloat
+    'mac_write_linker_maps%': 0,
+
+    # The default type of gtest.
+    'gtest_target_type%': 'executable',
+
+    # Enable sampling based profiler.
+    # See http://google-perftools.googlecode.com/svn/trunk/doc/cpuprofile.html
+    'profiling%': '0',
+    # Profile without optimizing out stack frames when profiling==1.
+    'profiling_full_stack_frames%': '0',
+
+    # And if we want to dump symbols for Breakpad-enabled builds.
+    'linux_dump_symbols%': 0,
+    # And if we want to strip the binary after dumping symbols.
+    'linux_strip_binary%': 0,
+    # If we want stack unwind support for backtrace().
+    'debug_unwind_tables%': 1,
+    'release_unwind_tables%': 1,
+
+    # Override where to find binutils
+    'binutils_version%': 0,
+    'binutils_dir%': '',
+
+    # Enable TCMalloc.
+    # Default of 'use_allocator' is set to 'none' if OS=='android' later.
+    'use_allocator%': 'tcmalloc',
+
+    # Set to 1 to link against gsettings APIs instead of using dlopen().
+    'linux_link_gsettings%': 0,
+
+    # Enable use of OpenMAX DL FFT routines.
+    'use_openmax_dl_fft%': '<(use_openmax_dl_fft)',
+
+    # Enable new NPDevice API.
+    'enable_new_npdevice_api%': 0,
+
+    # .gyp files or targets should set chromium_code to 1 if they build
+    # Chromium-specific code, as opposed to external code.  This variable is
+    # used to control such things as the set of warnings to enable, and
+    # whether warnings are treated as errors.
+    'chromium_code%': 0,
+
+    # Disable fatal linker warnings, similarly to how we make it possible
+    # to disable -Werror (e.g. for different toolchain versions).
+    'disable_fatal_linker_warnings%': 0,
+
+    'release_valgrind_build%': 0,
+
+    # TODO(thakis): Make this a blacklist instead, http://crbug.com/101600
+    'enable_wexit_time_destructors%': 0,
+
+    # Set to 1 to compile with the OpenGL ES 2.0 conformance tests.
+    'internal_gles2_conform_tests%': 0,
+
+    # Set to 1 to compile with the Khronos GL-CTS conformance tests.
+    'internal_khronos_glcts_tests%': 0,
+
+    # Set to 1 to compile the filter fuzzer.
+    'internal_filter_fuzzer%': 0,
+
+    # NOTE: When these end up in the Mac bundle, we need to replace '-' for '_'
+    # so Cocoa is happy (http://crbug.com/20441).
+    'locales': [
+      'am', 'ar', 'bg', 'bn', 'ca', 'cs', 'da', 'de', 'el', 'en-GB',
+      'en-US', 'es-419', 'es', 'et', 'fa', 'fi', 'fil', 'fr', 'gu', 'he',
+      'hi', 'hr', 'hu', 'id', 'it', 'ja', 'kn', 'ko', 'lt', 'lv',
+      'ml', 'mr', 'ms', 'nb', 'nl', 'pl', 'pt-BR', 'pt-PT', 'ro', 'ru',
+      'sk', 'sl', 'sr', 'sv', 'sw', 'ta', 'te', 'th', 'tr', 'uk',
+      'vi', 'zh-CN', 'zh-TW',
+    ],
+
+    # Pseudo locales are special locales which are used for testing and
+    # debugging. They don't get copied to the final app. For more info,
+    # check out https://www.chromium.org/developers/testing/fake-bidi
+    'pseudo_locales': [
+      'fake-bidi',
+    ],
+
+    'grit_defines': [],
+
+    # If debug_devtools is set to 1, JavaScript files for DevTools are
+    # stored as is and loaded from disk. Otherwise, a concatenated file
+    # is stored in resources.pak. It is still possible to load JS files
+    # from disk by passing --debug-devtools cmdline switch.
+    'debug_devtools%': 0,
+
+    # The Java Bridge is not compiled in by default.
+    'java_bridge%': 0,
+
+    # Code signing for iOS binaries.  The bots need to be able to disable this.
+    'chromium_ios_signing%': 1,
+
+    # Identity to use for code signing of iOS binaries.  Change this on machines
+    # with multiple identities in their security keychain.
+    'chromium_ios_signing_identity%': 'iPhone Developer',
+
+    # This flag is only used when disable_nacl==0 and disables all those
+    # subcomponents which would require the installation of a native_client
+    # untrusted toolchain.
+    'disable_nacl_untrusted%': 0,
+
+    # PNaCl toolchain does not support sanitizers. Disable by default.
+    'enable_nacl_nonsfi_test%': 0,
+
+    # Disable Dart by default.
+    'enable_dart%': 0,
+
+    # Copy out the setting of disable_nacl.
+    'disable_nacl%': '<(disable_nacl)',
+
+    # Native Client toolchains, enabled by default.
+    'disable_pnacl%': '<(disable_pnacl)',
+    'disable_newlib%': '<(disable_newlib)',
+
+    # Whether to build full debug version for Debug configuration on Android.
+    # Compared to full debug version, the default Debug configuration on Android
+    # has no full v8 debug, has size optimization and linker gc section, so that
+    # we can build a debug version with acceptable size and performance.
+    'android_full_debug%': 0,
+
+    # Contains data about the attached devices for gyp_managed_install.
+    'build_device_config_path': '<(PRODUCT_DIR)/build_devices.cfg',
+
+    'wix_exists': '<!pymod_do_main(dir_exists "<(wix_path)")',
+
+    'windows_sdk_path%': 'C:/Program Files (x86)/Windows Kits/10',
+    'directx_sdk_default_path': '<(DEPTH)/third_party/directxsdk/files',
+
+    # Whether we are using the rlz library or not.  Platforms like Android send
+    # rlz codes for searches but do not use the library.
+    'enable_rlz_support%': 0,
+    'enable_rlz%': 0,
+
+    # Turns on the i18n support in V8.
+    'v8_enable_i18n_support': 1,
+
+    # Compile the v8 shell for the host toolset.
+    'v8_toolset_for_shell': 'host',
+
+    # V8 extras
+    # Adding V8 extras files requires API owners review
+    # Be sure to synchronize with build/module_args/v8.gni
+
+    'v8_extra_library_files': [
+      '../third_party/WebKit/Source/core/streams/ByteLengthQueuingStrategy.js',
+      '../third_party/WebKit/Source/core/streams/CountQueuingStrategy.js',
+      '../third_party/WebKit/Source/core/streams/ReadableStream.js',
+    ],
+    'v8_experimental_extra_library_files': [
+    ],
+
+    # Use brlapi from brltty for braille display support.
+    'use_brlapi%': 0,
+
+    # Relative path to icu.gyp from this file.
+    'icu_gyp_path': '../third_party/icu/icu.gyp',
+
+    # IPC fuzzer is disabled by default.
+    'enable_ipc_fuzzer%': 0,
+
+    # Force disable libstdc++ debug mode.
+    'disable_glibcxx_debug%': 0,
+
+    # Support ChromeOS touchpad gestures with ozone.
+    'use_evdev_gestures%': 0,
+
+    # Default ozone platform (if no --ozone-platform flag).
+    'ozone_platform%': "",
+
+    # Ozone platforms to include in the build.
+    'ozone_platform_caca%': 0,
+    'ozone_platform_cast%': 0,
+    'ozone_platform_gbm%': 0,
+    'ozone_platform_headless%': 0,
+    'ozone_platform_wayland%': 0,
+
+    # Experiment: http://crbug.com/426914
+    'envoy%': 0,
+
+    # Used to set libjpeg_gyp_path. Chrome OS ui/gfx/gfx.gyp uses the IJG path
+    # for robust login screen decoding.
+    'libjpeg_ijg_gyp_path': '<(DEPTH)/third_party/libjpeg/libjpeg.gyp',
+    'libjpeg_turbo_gyp_path': '<(DEPTH)/third_party/libjpeg_turbo/libjpeg.gyp',
+
+    'conditions': [
+      # Enable the Syzygy optimization step for the official builds.
+      ['OS=="win" and buildtype=="Official" and syzyasan!=1 and clang!=1', {
+        'syzygy_optimize%': 1,
+      }, {
+        'syzygy_optimize%': 0,
+      }],
+      ['sanitizer_coverage==1', {
+        'sanitizer_coverage': 'edge,indirect-calls,8bit-counters',
+      }],
+      # Get binutils version so we can enable debug fission if we can.
+      ['os_posix==1 and OS!="mac" and OS!="ios"', {
+        'conditions': [
+          # compiler_version doesn't work with clang
+          # TODO(mithro): Land https://codereview.chromium.org/199793014/ so
+          # compiler_version works with clang.
+          # TODO(glider): set clang to 1 earlier for ASan and TSan builds so
+          # that it takes effect here.
+          ['clang==0 and asan==0 and lsan==0 and tsan==0 and msan==0 and ubsan==0 and ubsan_security==0 and ubsan_vptr==0', {
+            'binutils_version%': '<!pymod_do_main(compiler_version target assembler)',
+          }],
+          # On Android we know the binutils version in the toolchain.
+          ['OS=="android"', {
+            'binutils_version%': 222,
+          }],
+          ['host_arch=="x64"', {
+            'binutils_dir%': 'third_party/binutils/Linux_x64/Release/bin',
+          }],
+          ['host_arch=="ia32"', {
+            'binutils_dir%': 'third_party/binutils/Linux_ia32/Release/bin',
+          }],
+          # Our version of binutils in third_party/binutils
+          ['linux_use_bundled_binutils==1', {
+            'binutils_version%': 224,
+          }],
+        ],
+      }, {
+        'binutils_version%': 0,
+      }],
+      ['OS=="win" and "<!pymod_do_main(dir_exists <(directx_sdk_default_path))"=="True"', {
+        'directx_sdk_path%': '<(directx_sdk_default_path)',
+      }, {
+        'directx_sdk_path%': '$(DXSDK_DIR)',
+      }],
+      ['OS=="win"', {
+        'windows_driver_kit_path%': '$(WDK_DIR)',
+        'conditions': [
+          ['component!="shared_library"', {
+            'single_module_mode_handle_verifier%': 0,
+          }, {
+            'single_module_mode_handle_verifier%': 1,
+          }],
+        ],
+      }],
+      ['os_posix==1 and OS!="mac" and OS!="ios"', {
+        'conditions': [
+          ['target_arch=="mipsel" or target_arch=="mips64el"', {
+            'werror%': '',
+            'disable_nacl%': 1,
+            'nacl_untrusted_build%': 0,
+            'use_allocator%': 'none',
+          }],
+          # Use a 64-bit linker to avoid running out of address space. The
+          # buildbots should have a 64-bit kernel and a 64-bit libc installed.
+          ['host_arch=="ia32" and target_arch=="ia32"', {
+            # TODO(thestig) This is a horrible way to force the desired
+            # configuration. Our gyp variable scoping is likely wrong and
+            # needs to be cleaned up. The GN configuration should be changed
+            # to match.
+            'binutils_version%': 224,
+            'linux_use_bundled_binutils%': '1',
+            'linux_use_bundled_gold%': '1',
+            'binutils_dir%': 'third_party/binutils/Linux_x64/Release/bin',
+          }],
+          # All Chrome builds have breakpad symbols, but only process the
+          # symbols from official builds.
+          ['(branding=="Chrome" and buildtype=="Official")', {
+            'linux_dump_symbols%': 1,
+
+            # Omit unwind support in official release builds to save space. We
+            # can use breakpad for these builds.
+            'release_unwind_tables%': 0,
+          }],
+        ],
+      }],  # os_posix==1 and OS!="mac" and OS!="ios"
+      ['OS=="ios"', {
+        'disable_nacl%': 1,
+        'icu_use_data_file_flag%': 1,
+        'enable_web_speech%': 0,
+        'use_system_libxml%': 1,
+        'use_system_sqlite%': 1,
+        'locales==': [
+          'ar', 'ca', 'cs', 'da', 'de', 'el', 'en-GB', 'en-US', 'es', 'es-MX',
+          'fi', 'fr', 'he', 'hi', 'hr', 'hu', 'id', 'it', 'ja', 'ko', 'ms',
+          'nb', 'nl', 'pl', 'pt', 'pt-PT', 'ro', 'ru', 'sk', 'sv', 'th', 'tr',
+          'uk', 'vi', 'zh-CN', 'zh-TW',
+        ],
+
+        # iOS SDK and deployment target support.  The |ios_sdk| value is left
+        # blank so that when it is set in the project files it will be the
+        # "current" iOS SDK.  Forcing a specific SDK even if it is "current"
+        # causes Xcode to spit out a warning for every single project file for
+        # not using the "current" SDK.
+        'ios_sdk%': '',
+        'ios_sdk_path%': '',
+        'ios_deployment_target%': '9.0',
+
+        'conditions': [
+          # ios_product_name is set to the name of the .app bundle as it should
+          # appear on disk.
+          ['branding=="Chrome"', {
+            'ios_product_name%': 'Chrome',
+          }, { # else: branding!="Chrome"
+            'ios_product_name%': 'Chromium',
+          }],
+          ['branding=="Chrome" and buildtype=="Official"', {
+            'ios_breakpad%': 1,
+          }, { # else: branding!="Chrome" or buildtype!="Official"
+            'ios_breakpad%': 0,
+          }],
+        ],
+      }],  # OS=="ios"
+      ['OS=="android"', {
+        # Location of Android NDK.
+        'variables': {
+          'variables': {
+            # Standard libraries can use the relative path to the NDK.
+            'android_ndk_root%': '../../third_party/android_tools/ndk/',
+            # Unfortunately, it is required to use the absolute path to the SDK
+            # because it us passed to ant which uses a different relative path
+            # from GYP.
+            'android_sdk_root%': '<!(cd <(DEPTH) && pwd -P)/third_party/android_tools/sdk/',
+            # Similarly, gdbserver and the Android toolchain need to use the
+            # absolute path to the NDK because they are used at different levels
+            # in the GYP files.
+            'android_ndk_absolute_root%': '<!(cd <(DEPTH) && pwd -P)/third_party/android_tools/ndk/',
+            'android_host_arch%': '<!(uname -m)',
+            # Version of the NDK. Used to ensure full rebuilds on NDK rolls.
+            'android_ndk_version%': 'r10e',
+            # Android API-level of the SDK used for compilation.
+            'android_sdk_version%': '23',
+            'android_sdk_build_tools_version%': '23.0.1',
+            'host_os%': "<!(uname -s | sed -e 's/Linux/linux/;s/Darwin/mac/')",
+
+            'conditions': [
+              # Figure this out early since it needs symbols from libgcc.a, so it
+              # has to be before that in the set of libraries.
+              # ASan needs to dynamically link to libc++ even in static builds so
+              # that it can interpose operator new.
+              ['component=="shared_library" or asan==1', {
+                  'android_libcpp_library': 'c++_shared',
+                  'android_must_copy_system_libraries': 1,
+              }, {
+                  'android_libcpp_library': 'c++_static',
+                  'android_must_copy_system_libraries': 0,
+              }],
+            ],
+
+          },
+          # Copy conditionally-set variables out one scope.
+          'android_ndk_root%': '<(android_ndk_root)',
+          'android_ndk_absolute_root%': '<(android_ndk_absolute_root)',
+          'android_ndk_version%': '<(android_ndk_version)',
+          'android_sdk_root%': '<(android_sdk_root)',
+          'android_sdk_version%': '<(android_sdk_version)',
+          'android_sdk_build_tools_version%': '<(android_sdk_build_tools_version)',
+          'android_libcpp_root': '<(android_ndk_root)/sources/cxx-stl/llvm-libc++',
+          'android_libcpp_library': '<(android_libcpp_library)',
+          'android_must_copy_system_libraries': '<(android_must_copy_system_libraries)',
+          'host_os%': '<(host_os)',
+
+          'android_sdk%': '<(android_sdk_root)/platforms/android-<(android_sdk_version)',
+          # Android SDK build tools (e.g. dx, aidl)
+          'android_sdk_tools%': '<(android_sdk_root)/build-tools/<(android_sdk_build_tools_version)',
+
+          # Android API level 16 is JB (Android 4.1) which is the minimum
+          # platform requirement for Chrome on Android, we use it for native
+          # code compilation.
+          'conditions': [
+            ['target_arch == "ia32"', {
+              'android_app_abi%': 'x86',
+              'android_gdbserver%': '<(android_ndk_absolute_root)/prebuilt/android-x86/gdbserver/gdbserver',
+              'android_ndk_sysroot%': '<(android_ndk_root)/platforms/android-16/arch-x86',
+              'android_ndk_lib_dir%': 'usr/lib',
+              'android_toolchain%': '<(android_ndk_absolute_root)/toolchains/x86-4.9/prebuilt/<(host_os)-<(android_host_arch)/bin',
+            }],
+            ['target_arch == "x64"', {
+              'android_app_abi%': 'x86_64',
+              'android_gdbserver%': '<(android_ndk_absolute_root)/prebuilt/android-x86_64/gdbserver/gdbserver',
+              'android_ndk_sysroot%': '<(android_ndk_root)/platforms/android-21/arch-x86_64',
+              'android_ndk_lib_dir%': 'usr/lib64',
+              'android_toolchain%': '<(android_ndk_absolute_root)/toolchains/x86_64-4.9/prebuilt/<(host_os)-<(android_host_arch)/bin',
+            }],
+            ['target_arch=="arm"', {
+              'conditions': [
+                ['arm_version<7', {
+                  'android_app_abi%': 'armeabi',
+                }, {
+                  'android_app_abi%': 'armeabi-v7a',
+                }],
+              ],
+              'android_gdbserver%': '<(android_ndk_absolute_root)/prebuilt/android-arm/gdbserver/gdbserver',
+              'android_ndk_sysroot%': '<(android_ndk_root)/platforms/android-16/arch-arm',
+              'android_ndk_lib_dir%': 'usr/lib',
+              'android_toolchain%': '<(android_ndk_absolute_root)/toolchains/arm-linux-androideabi-4.9/prebuilt/<(host_os)-<(android_host_arch)/bin',
+            }],
+            ['target_arch == "arm64"', {
+              'android_app_abi%': 'arm64-v8a',
+              'android_gdbserver%': '<(android_ndk_absolute_root)/prebuilt/android-arm64/gdbserver/gdbserver',
+              'android_ndk_sysroot%': '<(android_ndk_root)/platforms/android-21/arch-arm64',
+              'android_ndk_lib_dir%': 'usr/lib',
+              'android_toolchain%': '<(android_ndk_absolute_root)/toolchains/aarch64-linux-android-4.9/prebuilt/<(host_os)-<(android_host_arch)/bin',
+            }],
+            ['target_arch == "mipsel"', {
+              'android_app_abi%': 'mips',
+              'android_gdbserver%': '<(android_ndk_absolute_root)/prebuilt/android-mips/gdbserver/gdbserver',
+              'android_ndk_sysroot%': '<(android_ndk_root)/platforms/android-16/arch-mips',
+              'android_ndk_lib_dir%': 'usr/lib',
+              'android_toolchain%': '<(android_ndk_absolute_root)/toolchains/mipsel-linux-android-4.9/prebuilt/<(host_os)-<(android_host_arch)/bin',
+            }],
+            ['target_arch == "mips64el"', {
+              'android_app_abi%': 'mips64',
+              'android_gdbserver%': '<(android_ndk_absolute_root)/prebuilt/android-mips64/gdbserver/gdbserver',
+              'android_ndk_sysroot%': '<(android_ndk_root)/platforms/android-21/arch-mips64',
+              'android_ndk_lib_dir%': 'usr/lib64',
+              'android_toolchain%': '<(android_ndk_absolute_root)/toolchains/mips64el-linux-android-4.9/prebuilt/<(host_os)-<(android_host_arch)/bin',
+            }],
+          ],
+        },
+        # Copy conditionally-set variables out one scope.
+        'android_app_abi%': '<(android_app_abi)',
+        'android_gdbserver%': '<(android_gdbserver)',
+        'android_ndk_root%': '<(android_ndk_root)',
+        'android_ndk_sysroot%': '<(android_ndk_sysroot)',
+        'android_ndk_version%': '<(android_ndk_version)',
+        'android_sdk_root%': '<(android_sdk_root)',
+        'android_sdk_version%': '<(android_sdk_version)',
+        'android_toolchain%': '<(android_toolchain)',
+
+        'android_ndk_include': '<(android_ndk_sysroot)/usr/include',
+        'android_ndk_lib': '<(android_ndk_sysroot)/<(android_ndk_lib_dir)',
+        'android_sdk_build_tools_version%': '<(android_sdk_build_tools_version)',
+        'android_sdk_tools%': '<(android_sdk_tools)',
+        'android_aapt_path%': '<(android_sdk_tools)/aapt',
+        'android_sdk%': '<(android_sdk)',
+        'android_sdk_jar%': '<(android_sdk)/android.jar',
+
+        'android_libcpp_root': '<(android_libcpp_root)',
+        'android_libcpp_library': '<(android_libcpp_library)',
+        'android_libcpp_include': '<(android_libcpp_root)/libcxx/include',
+        'android_libcpp_libs_dir%': '<(android_libcpp_root)/libs/<(android_app_abi)',
+        'android_must_copy_system_libraries': '<(android_must_copy_system_libraries)',
+        'host_os%': '<(host_os)',
+
+        # Location of the "objcopy" binary, used by both gyp and scripts.
+        'android_objcopy%' : '<!(/bin/echo -n <(android_toolchain)/*-objcopy)',
+
+        # Location of the "strip" binary, used by both gyp and scripts.
+        'android_strip%' : '<!(/bin/echo -n <(android_toolchain)/*-strip)',
+
+        # Location of the "readelf" binary.
+        'android_readelf%' : '<!(/bin/echo -n <(android_toolchain)/*-readelf)',
+
+        # Determines whether we should optimize JNI generation at the cost of
+        # breaking assumptions in the build system that when inputs have changed
+        # the outputs should always change as well.  This is meant purely for
+        # developer builds, to avoid spurious re-linking of native files.
+        'optimize_jni_generation%': '<(optimize_jni_generation)',
+
+        # Use OpenSSL's struct X509 to represent certificates.
+        'use_openssl_certs%': 1,
+
+        'proprietary_codecs%': '<(proprietary_codecs)',
+
+        'safe_browsing%': 2,
+
+        'enable_web_speech%': 0,
+        'java_bridge%': 1,
+        'use_allocator%': 'none',
+
+        # Disable Native Client.
+        'disable_nacl%': 1,
+
+        # Sessions are store separately in the Java side.
+        'enable_session_service%': 0,
+
+        'p2p_apis%' : 0,
+
+        'gtest_target_type%': 'shared_library',
+      }],  # OS=="android"
+      ['embedded==1', {
+        'use_system_fontconfig%': 0,
+      }, {
+        'use_system_fontconfig%': 1,
+      }],
+      ['chromecast==1', {
+        'conditions': [
+          ['target_arch=="arm"', {
+            'arm_arch%': '',
+            'arm_tune%': 'cortex-a9',
+            'arm_thumb%': 1,
+          }],
+          # TODO(dalecurtis): What audio codecs does Chromecast want here?  Sort
+          # out and add configs if necessary.  http://crbug.com/570754
+          ['OS!="android"', {
+            'ffmpeg_branding%': 'ChromeOS',
+          }],
+        ],
+      }],
+      ['OS=="linux"', {
+        'clang%': 1,
+        'conditions': [
+          ['target_arch=="arm64"', {
+            # Temporarily disable nacl and tcmalloc on arm64 linux to get
+            # rid of compilation errors.
+            'disable_nacl%': 1,
+            'use_allocator%': 'none',
+          }],
+        ],
+      }],  # OS=="mac"
+      ['OS=="mac"', {
+        'conditions': [
+          # All Chrome builds have breakpad symbols, but only process the
+          # symbols from official builds.
+          ['(branding=="Chrome" and buildtype=="Official")', {
+            'mac_strip_release%': 1,
+          }],
+        ],
+      }],  # OS=="mac"
+      ['OS=="mac" or OS=="ios"', {
+        'clang%': 1,
+
+        # On Mac and iOS we just use the default system allocator.
+        'use_allocator%': 'none',
+
+        'variables': {
+          # Mac OS X SDK and deployment target support.  The SDK identifies
+          # the version of the system headers that will be used, and
+          # corresponds to the MAC_OS_X_VERSION_MAX_ALLOWED compile-time
+          # macro.  "Maximum allowed" refers to the operating system version
+          # whose APIs are available in the headers.  The deployment target
+          # identifies the minimum system version that the built products are
+          # expected to function on.  It corresponds to the
+          # MAC_OS_X_VERSION_MIN_REQUIRED compile-time macro.  To ensure these
+          # macros are available, #include <AvailabilityMacros.h>.  Additional
+          # documentation on these macros is available at
+          # http://developer.apple.com/mac/library/technotes/tn2002/tn2064.html#SECTION3
+          # Chrome normally builds with the Mac OS X 10.10 SDK and sets the
+          # deployment target to 10.7.  Other projects, such as O3D, may
+          # override these defaults.
+
+          # Normally, mac_sdk_min is used to find an SDK that Xcode knows
+          # about that is at least the specified version. In official builds,
+          # the SDK must match mac_sdk_min exactly. If the SDK is installed
+          # someplace that Xcode doesn't know about, set mac_sdk_path to the
+          # path to the SDK; when set to a non-empty string, SDK detection
+          # based on mac_sdk_min will be bypassed entirely.
+          'mac_deployment_target%': '10.7',
+          'mac_sdk_min%': '10.10',
+          'mac_sdk_path%': '',
+        },
+
+        'mac_sdk_min': '<(mac_sdk_min)',
+        'mac_sdk_path': '<(mac_sdk_path)',
+        'mac_deployment_target': '<(mac_deployment_target)',
+
+        # Compile in Breakpad support by default so that it can be
+        # tested, even if it is not enabled by default at runtime.
+        'mac_breakpad_compiled_in%': 1,
+        'conditions': [
+          # mac_product_name is set to the name of the .app bundle as it should
+          # appear on disk.  This duplicates data from
+          # chrome/app/theme/chromium/BRANDING and
+          # chrome/app/theme/google_chrome/BRANDING, but is necessary to get
+          # these names into the build system.
+          ['branding=="Chrome"', {
+            'mac_product_name%': 'Google Chrome',
+          }, { # else: branding!="Chrome"
+            'mac_product_name%': 'Chromium',
+          }],
+          # Official mac builds require a specific OS X SDK, but iOS and
+          # non-official mac builds do not.
+          ['branding=="Chrome" and buildtype=="Official" and OS=="mac"', {
+            'mac_sdk%': '<!(python <(DEPTH)/build/mac/find_sdk.py --verify <(mac_sdk_min) --sdk_path=<(mac_sdk_path))',
+          }, {
+            'mac_sdk%': '<!(python <(DEPTH)/build/mac/find_sdk.py <(mac_sdk_min))',
+          }],
+          ['branding=="Chrome" and buildtype=="Official"', {
+            # Enable uploading crash dumps.
+            'mac_breakpad_uploads%': 1,
+            # Enable dumping symbols at build time for use by Mac Breakpad.
+            'mac_breakpad%': 1,
+            # Enable Keystone auto-update support.
+            'mac_keystone%': 1,
+          }, { # else: branding!="Chrome" or buildtype!="Official"
+            'mac_breakpad_uploads%': 0,
+            'mac_breakpad%': 0,
+            'mac_keystone%': 0,
+          }],
+        ],
+      }],  # OS=="mac" or OS=="ios"
+      ['OS=="win"', {
+        'conditions': [
+          # This is the architecture convention used in WinSDK paths.
+          ['target_arch=="ia32"', {
+            'winsdk_arch%': 'x86',
+          },{
+            'winsdk_arch%': '<(target_arch)',
+          }],
+          ['component=="shared_library"', {
+            'win_use_allocator_shim%': 0,
+          }],
+          ['component=="static_library"', {
+            # Turn on multiple dll by default on Windows when in static_library.
+            'chrome_multiple_dll%': 1,
+          }],
+          ['asan==1 or syzyasan==1', {
+            'win_use_allocator_shim%': 0,
+          }],
+          # The AddressSanitizer build should be a console program as it prints
+          # out stuff on stderr.
+          ['asan==1', {
+            'win_console_app%': 1,
+          }, {
+            'win_console_app%': 0,
+          }],
+          # Enable the Kasko reporter for syzyasan builds.
+          ['syzyasan==1', {
+            'kasko': 1,
+          }],
+          ['component=="shared_library"', {
+            # Not enabled for component=static_library because some targets
+            # are too large and the toolchain fails due to the size of the
+            # .obj files.
+            'incremental_chrome_dll%': 1,
+          }],
+          # Don't do incremental linking for large modules on 32-bit or when
+          # component=static_library as the toolchain fails due to the size of
+          # the .ilk files.
+          ['MSVS_OS_BITS==32 or component=="static_library"', {
+            'msvs_large_module_debug_link_mode%': '1',  # No
+          },{
+            'msvs_large_module_debug_link_mode%': '2',  # Yes
+          }],
+          ['chrome_pgo_phase!=0', {
+            'full_wpo_on_official%': 1,
+          }],
+        ],
+        'nacl_win64_defines': [
+          # This flag is used to minimize dependencies when building
+          # Native Client loader for 64-bit Windows.
+          'NACL_WIN64',
+        ],
+        # Need to include allocator target, but exclude tcmalloc files.
+        'use_allocator%': 'winheap',
+      }],
+
+      ['os_posix==1 and chromeos==0 and OS!="android" and OS!="ios" and embedded==0', {
+        'use_cups%': 1,
+      }, {
+        'use_cups%': 0,
+      }],
+
+      ['enable_plugins==1 and (OS=="linux" or OS=="mac" or OS=="win") and chromecast==0', {
+        'enable_pepper_cdms%': 1,
+      }, {
+        'enable_pepper_cdms%': 0,
+      }],
+
+      ['OS=="android" or chromecast==1', {
+        'enable_browser_cdms%': 1,
+      }, {
+        'enable_browser_cdms%': 0,
+      }],
+
+      # Native Client glibc toolchain is enabled except on mips
+      ['target_arch=="mipsel" or target_arch=="mips64el"', {
+        'disable_glibc%': 1,
+      }, {
+        'disable_glibc%': 0,
+      }],
+
+      # Set the relative path from this file to the GYP file of the JPEG
+      # library used by Chromium.
+      ['use_system_libjpeg==1 or use_libjpeg_turbo==0', {
+        # Configuration for using the system libjeg is here.
+        'libjpeg_gyp_path': '<(libjpeg_ijg_gyp_path)',
+      }, {
+        'libjpeg_gyp_path': '<(libjpeg_turbo_gyp_path)',
+      }],
+
+      # Options controlling the use of GConf (the classic GNOME configuration
+      # system) and GIO, which contains GSettings (the new GNOME config system).
+      ['chromeos==1 or embedded==1', {
+        'use_gconf%': 0,
+        'use_gio%': 0,
+      }, {
+        'use_gconf%': 1,
+        'use_gio%': 1,
+      }],
+
+      # Set up -D and -E flags passed into grit.
+      ['branding=="Chrome"', {
+        # TODO(mmoss) The .grd files look for _google_chrome, but for
+        # consistency they should look for google_chrome_build like C++.
+        'grit_defines': ['-D', '_google_chrome',
+                         '-E', 'CHROMIUM_BUILD=google_chrome'],
+      }, {
+        'grit_defines': ['-D', '_chromium',
+                         '-E', 'CHROMIUM_BUILD=chromium'],
+      }],
+      ['chromeos==1', {
+        'grit_defines': ['-D', 'chromeos', '-D', 'scale_factors=2x'],
+      }],
+      ['desktop_linux==1', {
+        'grit_defines': ['-D', 'desktop_linux'],
+      }],
+      ['toolkit_views==1', {
+        'grit_defines': ['-D', 'toolkit_views'],
+      }],
+      ['use_aura==1', {
+        'grit_defines': ['-D', 'use_aura'],
+      }],
+      ['use_ash==1', {
+        'grit_defines': ['-D', 'use_ash'],
+      }],
+      ['use_nss_certs==1', {
+        'grit_defines': ['-D', 'use_nss_certs'],
+      }],
+      ['use_ozone==1', {
+        'grit_defines': ['-D', 'use_ozone'],
+      }],
+      ['image_loader_extension==1', {
+        'grit_defines': ['-D', 'image_loader_extension'],
+      }],
+      ['use_titlecase_in_grd==1', {
+        'grit_defines': ['-D', 'use_titlecase'],
+      }],
+      ['OS=="android"', {
+        'grit_defines': [
+          '-t', 'android',
+          '-E', 'ANDROID_JAVA_TAGGED_ONLY=true',
+          '--no-output-all-resource-defines',
+        ],
+      }],
+      ['OS=="mac" or OS=="ios"', {
+        'grit_defines': ['-D', 'scale_factors=2x'],
+      }],
+      ['OS == "ios"', {
+        'variables': {
+          'enable_coverage%': 0,
+        },
+        'grit_defines': [
+          '-t', 'ios',
+          '--no-output-all-resource-defines',
+        ],
+
+        # Enable host builds.
+        'host_os%': "mac",
+
+        'conditions': [
+          # Use the version of clang shipped with Xcode when building official
+          # version of Chrome for iOS.
+          #
+          # TODO(eugenebut): Remove enable_coverage check once
+          # libclang_rt.profile_ios.a is bundled with Chromium's clang.
+          # http://crbug.com/450379
+          ['buildtype=="Official" or enable_coverage', {
+            'clang_xcode%': 1,
+          }],
+        ],
+      }],
+      ['enable_extensions==1', {
+        'grit_defines': ['-D', 'enable_extensions'],
+      }],
+      ['enable_plugins!=0', {
+        'grit_defines': ['-D', 'enable_plugins'],
+      }],
+      ['enable_basic_printing==1 or enable_print_preview==1', {
+        'grit_defines': ['-D', 'enable_printing'],
+      }],
+      ['enable_print_preview==1', {
+        'grit_defines': ['-D', 'enable_print_preview'],
+      }],
+      ['enable_themes==1', {
+        'grit_defines': ['-D', 'enable_themes'],
+      }],
+      ['enable_app_list==1', {
+        'grit_defines': ['-D', 'enable_app_list'],
+      }],
+      ['use_concatenated_impulse_responses==1', {
+        'grit_defines': ['-D', 'use_concatenated_impulse_responses'],
+      }],
+      ['enable_media_router==1', {
+        'grit_defines': ['-D', 'enable_media_router'],
+      }],
+      ['enable_webrtc==1', {
+        'grit_defines': ['-D', 'enable_webrtc'],
+      }],
+      ['enable_hangout_services_extension==1', {
+        'grit_defines': ['-D', 'enable_hangout_services_extension'],
+      }],
+      ['enable_task_manager==1', {
+        'grit_defines': ['-D', 'enable_task_manager'],
+      }],
+      ['notifications==1', {
+        'grit_defines': ['-D', 'enable_notifications'],
+      }],
+      ['mac_views_browser==1', {
+        'grit_defines': ['-D', 'mac_views_browser'],
+      }],
+      ['enable_resource_whitelist_generation==1 and OS!="win"', {
+        'grit_rc_header_format': ['-h', '#define {textual_id} _Pragma("whitelisted_resource_{numeric_id}") {numeric_id}'],
+      }],
+      ['enable_resource_whitelist_generation==1 and OS=="win"', {
+        'grit_rc_header_format': ['-h', '#define {textual_id} __pragma(message("whitelisted_resource_{numeric_id}")) {numeric_id}'],
+      }],
+      ['enable_mdns==1 or OS=="mac"', {
+        'grit_defines': ['-D', 'enable_service_discovery'],
+        'enable_service_discovery%': 1
+      }],
+      ['clang_use_chrome_plugins==1', {
+        'variables': {
+          'conditions': [
+            ['OS!="win"', {
+              'variables': {
+                'conditions': [
+                  ['OS=="mac" or OS=="ios"', {
+                    'clang_lib_path%': '<!(cd <(DEPTH) && pwd -P)/third_party/llvm-build/Release+Asserts/lib/libFindBadConstructs.dylib',
+                  }, { # OS != "mac" or OS != "ios"
+                    'clang_lib_path%': '<!(cd <(DEPTH) && pwd -P)/third_party/llvm-build/Release+Asserts/lib/libFindBadConstructs.so',
+                  }],
+                ],
+              },
+              'clang_dynlib_flags%': '-Xclang -load -Xclang <(clang_lib_path) ',
+            }, { # OS == "win"
+              # On Windows, the plugin is built directly into clang, so there's
+              # no need to load it dynamically.
+              'clang_dynlib_flags%': '',
+            }],
+            ['(OS=="android" or OS=="linux") and chromecast==0', {
+              'clang_plugin_check_ipc_arg': '-Xclang -plugin-arg-find-bad-constructs -Xclang check-ipc',
+            }, {
+              'clang_plugin_check_ipc_arg': '',
+            }],
+          ],
+          'clang_plugin_args%': '-Xclang -plugin-arg-find-bad-constructs -Xclang check-templates '
+          '-Xclang -plugin-arg-find-bad-constructs -Xclang follow-macro-expansion ',
+        },
+        # If you change these, also change build/config/clang/BUILD.gn.
+        'clang_chrome_plugins_flags%':
+          '<(clang_dynlib_flags)'
+          '-Xclang -add-plugin -Xclang find-bad-constructs <(clang_plugin_args) <(clang_plugin_check_ipc_arg)',
+      }],
+      ['asan==1 or msan==1 or lsan==1 or tsan==1', {
+        'clang%': 1,
+        'use_allocator%': 'none',
+        'use_sanitizer_options%': 1,
+      }],
+      ['(OS=="linux" or OS=="android") and asan==0 and msan==0 and lsan==0 and tsan==0 and build_for_tool==""', {
+        'use_experimental_allocator_shim%': 1,
+      }],
+      ['OS=="linux" and asan==0 and msan==0 and lsan==0 and tsan==0', {
+        # PNaCl toolchain Non-SFI build only supports linux OS build.
+        # Also, it does not support sanitizers.
+        'enable_nacl_nonsfi_test%': 1,
+      }],
+      ['asan==1 and OS=="linux" and chromeos==0', {
+        'use_custom_libcxx%': 1,
+      }],
+      ['ubsan==1', {
+        'clang%': 1,
+      }],
+      ['ubsan_security==1', {
+        'clang%': 1,
+      }],
+      ['ubsan_vptr==1', {
+        'clang%': 1,
+      }],
+      ['asan==1 and OS=="mac"', {
+        'mac_strip_release': 1,
+      }],
+      ['tsan==1', {
+        'use_custom_libcxx%': 1,
+      }],
+      ['msan==1', {
+        # Use a just-built, MSan-instrumented libc++ instead of the system-wide
+        # libstdc++. This is required to avoid false positive reports whenever
+        # the C++ standard library is used.
+        'use_custom_libcxx%': 1,
+        # Running the V8-generated code on an ARM simulator is a powerful hack
+        # that allows the tool to see the memory accesses from JITted code.
+        # Without this flag, JS code causes false positive reports from MSan.
+        'v8_target_arch': 'arm64',
+      }],
+
+      # Build tweaks for DrMemory.
+      # TODO(rnk): Combine with tsan config to share the builder.
+      # http://crbug.com/108155
+      ['build_for_tool=="drmemory"', {
+        # These runtime checks force initialization of stack vars which blocks
+        # DrMemory's uninit detection.
+        'win_debug_RuntimeChecks': '0',
+        # Iterator debugging is slow.
+        'win_debug_disable_iterator_debugging': '1',
+        # Try to disable optimizations that mess up stacks in a release build.
+        # DrM-i#1054 (https://github.com/DynamoRIO/drmemory/issues/1054)
+        # /O2 and /Ob0 (disable inline) cannot be used together because of a
+        # compiler bug, so we use /Ob1 instead.
+        'win_release_InlineFunctionExpansion': '1',
+        'win_release_OmitFramePointers': '0',
+        # Ditto for debug, to support bumping win_debug_Optimization.
+        'win_debug_InlineFunctionExpansion': 0,
+        'win_debug_OmitFramePointers': 0,
+        # Keep the code under #ifndef NVALGRIND.
+        'release_valgrind_build': 1,
+      }],
+
+      # RLZ library is used on Win, Mac, iOS and ChromeOS.
+      ['OS=="win" or OS=="mac" or OS=="ios" or chromeos==1', {
+        'enable_rlz_support%': 1,
+        'conditions': [
+          # RLZ is enabled for "Chrome" builds.
+          ['branding=="Chrome"', {
+            'enable_rlz%': 1,
+          }],
+        ],
+      }],
+
+      # Set default compiler flags depending on ARM version.
+      ['arm_version==6', {
+        'arm_arch%': 'armv6',
+        'arm_tune%': '',
+        'arm_fpu%': 'vfp',
+        'arm_float_abi%': 'softfp',
+        'arm_thumb%': 0,
+      }],
+      ['arm_version==7', {
+        'arm_arch%': 'armv7-a',
+        'arm_tune%': 'generic-armv7-a',
+        'conditions': [
+          ['arm_neon==1', {
+            'arm_fpu%': 'neon',
+          }, {
+            'arm_fpu%': 'vfpv3-d16',
+          }],
+          ['OS=="android"', {
+            'arm_float_abi%': 'softfp',
+          }, {
+            'arm_float_abi%': 'hard',
+          }],
+        ],
+        'arm_thumb%': 1,
+      }],
+
+      # Set default compiler flags for MIPS floating-point support.
+      ['target_arch=="mipsel"', {
+        'mips_float_abi%': 'hard',
+      }],
+      ['target_arch=="mipsel" and mips_arch_variant=="r2"', {
+        'mips_fpu_mode%': 'fp32',
+      }, {
+        'mips_fpu_mode%': '',
+      }],
+
+      # Enable brlapi by default for chromeos.
+      ['chromeos==1', {
+        'use_brlapi%': 1,
+      }],
+
+      ['use_ozone==1 and ozone_auto_platforms==1', {
+        # Use headless as the default platform.
+        'ozone_platform%': 'headless',
+        'ozone_platform_headless%': 1,
+        'conditions': [
+          ['chromecast==1', {
+            'ozone_platform_cast%': 1,
+            'conditions': [
+              # For desktop non-audio Chromecast builds, run with
+              # --ozone-platform=x11
+              # TODO(slan|halliwell): Make the default platform "cast" on
+              # desktop non-audio builds too.
+              ['is_cast_desktop_build==1 and disable_display==0', {
+                # Use GN instead. 
+              }, {
+                'ozone_platform%': 'cast',
+              }],
+            ],
+          }, {  # chromecast!=1
+            # Build all platforms whose deps are in install-build-deps.sh.
+            # Only these platforms will be compile tested by buildbots.
+            'conditions': [
+              ['chromeos==1', {
+                'ozone_platform_gbm%': 1,
+              }],
+            ],
+          }],
+        ],
+      }],
+
+      ['desktop_linux==1 and use_aura==1 and use_x11==1', {
+        'use_clipboard_aurax11%': 1,
+      }],
+
+      ['OS=="win" and use_goma==1', {
+        # goma doesn't support pch yet.
+        'chromium_win_pch': 0,
+        # goma doesn't support PDB yet, so win_z7=1 or fastbuild=1.
+        'conditions': [
+          ['win_z7==0 and fastbuild==0', {
+            'fastbuild': 1,
+          }],
+        ],
+      }],
+
+      ['host_clang==1', {
+        'host_cc': '<(make_clang_dir)/bin/clang',
+        'host_cxx': '<(make_clang_dir)/bin/clang++',
+      }, {
+        'host_cc': '<!(which gcc)',
+        'host_cxx': '<!(which g++)',
+      }],
+
+      # The seccomp-bpf sandbox is only supported on five architectures
+      # currently.
+      # Do not disable seccomp_bpf anywhere without talking to
+      # security@chromium.org!
+      ['((OS=="linux" or OS=="android") and '
+           '(target_arch=="ia32" or target_arch=="x64" or '
+             'target_arch=="arm" or target_arch=="mipsel" or '
+             'target_arch=="arm64"))', {
+         'use_seccomp_bpf%': 1,
+      }, {
+         'use_seccomp_bpf%': 0,
+      }],
+
+      ['cfi_vptr==1', {
+        'use_lto%': 1,
+      }],
+
+      ['branding=="Chrome" and buildtype=="Official"', {
+        'enable_hangout_services_extension%': 1,
+      }, {
+        'enable_hangout_services_extension%': 0,
+      }],
+    ],
+
+    # The path to the ANGLE library.
+    'angle_path': '<(DEPTH)/third_party/angle',
+
+    # List of default apps to install in new profiles.  The first list contains
+    # the source files as found in svn.  The second list, used only for linux,
+    # contains the destination location for each of the files.  When a crx
+    # is added or removed from the list, the chrome/browser/resources/
+    # default_apps/external_extensions.json file must also be updated.
+    #
+    # README: GN version of these is in the target //chrome:default_apps
+    # (there's no global variable like in GYP). Be sure to update that target
+    # if you change these lists!
+    'default_apps_list': [
+      'browser/resources/default_apps/external_extensions.json',
+      'browser/resources/default_apps/gmail.crx',
+      'browser/resources/default_apps/youtube.crx',
+      'browser/resources/default_apps/drive.crx',
+      'browser/resources/default_apps/docs.crx',
+    ],
+    'default_apps_list_linux_dest': [
+      '<(PRODUCT_DIR)/default_apps/external_extensions.json',
+      '<(PRODUCT_DIR)/default_apps/gmail.crx',
+      '<(PRODUCT_DIR)/default_apps/youtube.crx',
+      '<(PRODUCT_DIR)/default_apps/drive.crx',
+      '<(PRODUCT_DIR)/default_apps/docs.crx',
+    ],
+
+    # Whether to allow building of the GPU-related isolates.
+    'archive_gpu_tests%': 0,
+
+     # Whether to allow building of chromoting related isolates.
+    'archive_chromoting_tests%': 0,
+
+    # Whether to allow building of Media Router related isolates.
+    'archive_media_router_tests%': 0,
+  },
+  'target_defaults': {
+    'variables': {
+      # The condition that operates on chromium_code is in a target_conditions
+      # section, and will not have access to the default fallback value of
+      # chromium_code at the top of this file, or to the chromium_code
+      # variable placed at the root variables scope of .gyp files, because
+      # those variables are not set at target scope.  As a workaround,
+      # if chromium_code is not set at target scope, define it in target scope
+      # to contain whatever value it has during early variable expansion.
+      # That's enough to make it available during target conditional
+      # processing.
+      'chromium_code%': '<(chromium_code)',
+
+      'component%': '<(component)',
+
+      'chromecast%': '<(chromecast)',
+
+      # See http://msdn.microsoft.com/en-us/library/aa652360(VS.71).aspx
+      'win_release_Optimization%': '2', # 2 = /O2
+      'win_debug_Optimization%': '0',   # 0 = /Od
+
+      # See http://msdn.microsoft.com/en-us/library/2kxx5t2c(v=vs.80).aspx
+      # Tri-state: blank is default, 1 on, 0 off
+      'win_release_OmitFramePointers%': '0',
+      # Tri-state: blank is default, 1 on, 0 off
+      'win_debug_OmitFramePointers%': '',
+
+      # See http://msdn.microsoft.com/en-us/library/8wtf2dfz(VS.71).aspx
+      'win_debug_RuntimeChecks%': '3',    # 3 = all checks enabled, 0 = off
+
+      # See http://msdn.microsoft.com/en-us/library/47238hez(VS.71).aspx
+      'win_debug_InlineFunctionExpansion%': '',    # empty = default, 0 = off,
+      'win_release_InlineFunctionExpansion%': '2', # 1 = only __inline, 2 = max
+
+      # VS inserts quite a lot of extra checks to algorithms like
+      # std::partial_sort in Debug build which make them O(N^2)
+      # instead of O(N*logN). This is particularly slow under memory
+      # tools like ThreadSanitizer so we want it to be disablable.
+      # See http://msdn.microsoft.com/en-us/library/aa985982(v=VS.80).aspx
+      'win_debug_disable_iterator_debugging%': '0',
+
+      # An application manifest fragment to declare compatibility settings for
+      # 'executable' targets. Ignored in other target type.
+      'win_exe_compatibility_manifest%':
+          '<(DEPTH)\\build\\win\\compatibility.manifest',
+
+      'release_extra_cflags%': '',
+      'debug_extra_cflags%': '',
+
+      'release_valgrind_build%': '<(release_valgrind_build)',
+
+      # the non-qualified versions are widely assumed to be *nix-only
+      'win_release_extra_cflags%': '',
+      'win_debug_extra_cflags%': '',
+
+      # TODO(thakis): Make this a blacklist instead, http://crbug.com/101600
+      'enable_wexit_time_destructors%': '<(enable_wexit_time_destructors)',
+
+      # Only used by Windows build for now.  Can be used to build into a
+      # differet output directory, e.g., a build_dir_prefix of VS2010_ would
+      # output files in src/build/VS2010_{Debug,Release}.
+      'build_dir_prefix%': '',
+
+      # Targets are by default not nacl untrusted code.
+      'nacl_untrusted_build%': 0,
+
+      'pnacl_compile_flags': [
+        # pnacl uses the clang compiler so we need to suppress all the
+        # same warnings as we do for clang.
+        # TODO(sbc): Remove these if/when they are removed from the clang
+        # build.
+        '-Wno-unused-function',
+        '-Wno-char-subscripts',
+        '-Wno-c++11-extensions',
+        '-Wno-unnamed-type-template-args',
+      ],
+
+      # By default, Android targets have their exported JNI symbols stripped,
+      # so we test the manual JNI registration code paths that are required
+      # when using the crazy linker. To allow use of native JNI exports (lazily
+      # resolved by the JVM), targets can enable this variable, which will stop
+      # the stripping from happening. Only targets which do not need to be
+      # compatible with the crazy linker are permitted to set this.
+      'use_native_jni_exports%': 0,
+
+      'conditions': [
+        ['OS=="win" and component=="shared_library"', {
+          # See http://msdn.microsoft.com/en-us/library/aa652367.aspx
+          'win_release_RuntimeLibrary%': '2', # 2 = /MD (nondebug DLL)
+          'win_debug_RuntimeLibrary%': '3',   # 3 = /MDd (debug DLL)
+        }, {
+          # See http://msdn.microsoft.com/en-us/library/aa652367.aspx
+          'win_release_RuntimeLibrary%': '0', # 0 = /MT (nondebug static)
+          'win_debug_RuntimeLibrary%': '1',   # 1 = /MTd (debug static)
+        }],
+        ['OS=="ios"', {
+          # See http://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Optimize-Options.html
+          'mac_release_optimization%': 's', # Use -Os unless overridden
+          'mac_debug_optimization%': '0',   # Use -O0 unless overridden
+        }, {
+          # See http://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Optimize-Options.html
+          'mac_release_optimization%': '2', # Use -O2 unless overridden
+          'mac_debug_optimization%': '0',   # Use -O0 unless overridden
+        }],
+        ['OS=="android"', {
+          'host_os%': '<(host_os)',  # See comment above chromium_code.
+        }],
+      ],
+      'clang_warning_flags': [
+        '-Wheader-hygiene',
+
+        # TODO(thakis): Consider -Wloop-analysis (turns on
+        # -Wrange-loop-analysis too).
+
+        # Don't die on dtoa code that uses a char as an array index.
+        # This is required solely for base/third_party/dmg_fp/dtoa.cc.
+        '-Wno-char-subscripts',
+
+        # TODO(thakis): This used to be implied by -Wno-unused-function,
+        # which we no longer use. Check if it makes sense to remove
+        # this as well. http://crbug.com/316352
+        '-Wno-unneeded-internal-declaration',
+
+        # Warns on switches on enums that cover all enum values but
+        # also contain a default: branch. Chrome is full of that.
+        '-Wno-covered-switch-default',
+
+        # Warns when a const char[] is converted to bool.
+        '-Wstring-conversion',
+
+        # C++11-related flags:
+
+        # This warns on using ints as initializers for floats in
+        # initializer lists (e.g. |int a = f(); CGSize s = { a, a };|),
+        # which happens in several places in chrome code. Not sure if
+        # this is worth fixing.
+        '-Wno-c++11-narrowing',
+
+        # Clang considers the `register` keyword as deprecated, but e.g.
+        # code generated by flex (used in angle) contains that keyword.
+        # http://crbug.com/255186
+        '-Wno-deprecated-register',
+
+        # TODO(hans): Get this cleaned up, http://crbug.com/428099
+        '-Wno-inconsistent-missing-override',
+
+        # TODO(thakis): Enable this, crbug.com/507717
+        '-Wno-shift-negative-value',
+
+        # TODO(thakis): https://crbug.com/604888
+        '-Wno-undefined-var-template',
+
+        # TODO(thakis): https://crbug.com/617318
+        '-Wno-nonportable-include-path',
+      ],
+    },
+    'includes': [ 'set_clang_warning_flags.gypi', ],
+    'defines': [
+      # Don't use deprecated V8 APIs anywhere.
+      'V8_DEPRECATION_WARNINGS',
+    ],
+    'include_dirs': [
+      '<(SHARED_INTERMEDIATE_DIR)',
+    ],
+    'conditions': [
+      ['OS=="mac"', {
+        # When compiling Objective C, warns if a method is used whose
+        # availability is newer than the deployment target.
+        'xcode_settings': { 'WARNING_CFLAGS': ['-Wpartial-availability']},
+      }],
+      ['(OS=="mac" or OS=="ios") and asan==1', {
+        'dependencies': [
+          '<(DEPTH)/build/mac/asan.gyp:asan_dynamic_runtime',
+        ],
+      }],
+      ['OS=="win" and asan==1 and component=="shared_library"', {
+        'dependencies': [
+          '<(DEPTH)/build/win/asan.gyp:asan_dynamic_runtime',
+        ],
+      }],
+      ['branding=="Chrome"', {
+        'defines': ['GOOGLE_CHROME_BUILD'],
+      }, {  # else: branding!="Chrome"
+        'defines': ['CHROMIUM_BUILD'],
+      }],
+      ['OS=="mac" and component=="shared_library"', {
+        'xcode_settings': {
+          'DYLIB_INSTALL_NAME_BASE': '@rpath',
+          'LD_RUNPATH_SEARCH_PATHS': [
+            # For unbundled binaries.
+            '@loader_path/.',
+            # For bundled binaries, to get back from Binary.app/Contents/MacOS.
+            '@loader_path/../../..',
+          ],
+        },
+      }],
+      ['clang==1 or host_clang==1', {
+        # This is here so that all files get recompiled after a clang roll and
+        # when turning clang on or off.
+        # (defines are passed via the command line, and build systems rebuild
+        # things when their commandline changes). Nothing should ever read this
+        # define.
+        'defines': ['CR_CLANG_REVISION=<!(python <(DEPTH)/tools/clang/scripts/update.py --print-revision)'],
+      }],
+      ['enable_rlz==1', {
+        'defines': ['ENABLE_RLZ'],
+      }],
+      ['component=="shared_library"', {
+        'defines': ['COMPONENT_BUILD'],
+      }],
+      ['ui_compositor_image_transport==1', {
+        'defines': ['UI_COMPOSITOR_IMAGE_TRANSPORT'],
+      }],
+      ['use_aura==1', {
+        'defines': ['USE_AURA=1'],
+      }],
+      ['use_ash==1', {
+        'defines': ['USE_ASH=1'],
+      }],
+      ['use_pango==1', {
+        'defines': ['USE_PANGO=1'],
+      }],
+      ['use_cairo==1', {
+        'defines': ['USE_CAIRO=1'],
+      }],
+      ['use_cras==1', {
+        'defines': ['USE_CRAS=1'],
+      }],
+      ['use_ozone==1', {
+        'defines': ['USE_OZONE=1'],
+      }],
+      ['use_default_render_theme==1', {
+        'defines': ['USE_DEFAULT_RENDER_THEME=1'],
+      }],
+      ['use_libjpeg_turbo==1', {
+        'defines': ['USE_LIBJPEG_TURBO=1'],
+      }],
+      ['use_x11==1', {
+        'defines': ['USE_X11=1'],
+      }],
+      ['use_clipboard_aurax11==1', {
+        'defines': ['USE_CLIPBOARD_AURAX11=1'],
+      }],
+      ['image_loader_extension==1', {
+        'defines': ['IMAGE_LOADER_EXTENSION=1'],
+      }],
+      ['enable_webrtc==1', {
+        'defines': ['ENABLE_WEBRTC=1'],
+      }],
+      ['enable_media_router==1', {
+        'defines': ['ENABLE_MEDIA_ROUTER=1'],
+      }],
+      ['proprietary_codecs==1', {
+        'defines': ['USE_PROPRIETARY_CODECS'],
+      }],
+      ['enable_viewport==1', {
+        'defines': ['ENABLE_VIEWPORT'],
+      }],
+      ['enable_pepper_cdms==1', {
+        'defines': ['ENABLE_PEPPER_CDMS'],
+      }],
+      ['enable_browser_cdms==1', {
+        'defines': ['ENABLE_BROWSER_CDMS'],
+      }],
+      ['notifications==1', {
+        'defines': ['ENABLE_NOTIFICATIONS'],
+      }],
+      ['enable_wayland_server==1', {
+        'defines': ['ENABLE_WAYLAND_SERVER=1'],
+      }],
+      ['enable_wifi_display==1', {
+        'defines': ['ENABLE_WIFI_DISPLAY=1'],
+      }],
+      ['use_udev==1', {
+        'defines': ['USE_UDEV'],
+      }],
+      ['use_external_popup_menu==1', {
+        'defines': ['USE_EXTERNAL_POPUP_MENU'],
+      }],
+      ['fastbuild!=0', {
+        'xcode_settings': {
+          'GCC_GENERATE_DEBUGGING_SYMBOLS': 'NO',
+        },
+        'conditions': [
+          ['OS=="win" and fastbuild==2', {
+            # Completely disable debug information.
+            'msvs_settings': {
+              'VCLinkerTool': {
+                'GenerateDebugInformation': 'false',
+              },
+              'VCCLCompilerTool': {
+                'DebugInformationFormat': '0',
+              },
+            },
+          }],
+          ['OS=="win" and fastbuild==1', {
+            'msvs_settings': {
+              'VCLinkerTool': {
+                # This tells the linker to generate .pdbs, so that
+                # we can get meaningful stack traces.
+                'GenerateDebugInformation': 'true',
+              },
+              'VCCLCompilerTool': {
+                # No debug info to be generated by compiler.
+                'DebugInformationFormat': '0',
+              },
+            },
+          }],
+          ['(OS=="android" or OS=="linux") and fastbuild==2', {
+            'variables': { 'debug_extra_cflags': '-g0', },
+          }],
+          ['(OS=="android" or OS=="linux") and fastbuild==1', {
+            # TODO(thakis): Change this to -g1 once http://crbug.com/456947 is
+            # fixed.
+            'variables': { 'debug_extra_cflags': '-g0', },
+          }],
+          # Android builds symbols on release by default, disable them.
+          ['OS=="android" and fastbuild==2', {
+            'variables': { 'release_extra_cflags': '-g0', },
+          }],
+          ['OS=="android" and fastbuild==1', {
+            # TODO(thakis): Change this to -g1 once http://crbug.com/456947 is
+            # fixed.
+            'variables': { 'release_extra_cflags': '-g0', },
+          }],
+        ],
+      }],  # fastbuild!=0
+      ['dcheck_always_on!=0', {
+        'defines': ['DCHECK_ALWAYS_ON=1'],
+      }],  # dcheck_always_on!=0
+      ['tracing_like_official_build!=0', {
+        'defines': ['TRACING_IS_OFFICIAL_BUILD=1'],
+      }],  # tracing_like_official_build!=0
+      ['fieldtrial_testing_like_official_build==0 and branding!="Chrome"', {
+        'defines': ['FIELDTRIAL_TESTING_ENABLED'],
+      }],  # fieldtrial_testing_like_official_build==0 and branding!="Chrome"
+      ['OS=="win"', {
+        'defines': ['NO_TCMALLOC'],
+      }],
+      ['syzyasan==1', {
+        # SyzyAsan needs /PROFILE turned on to produce appropriate pdbs.
+        'msvs_settings': {
+          'VCLinkerTool': {
+            'Profile': 'true',
+          },
+        },
+        'defines': [
+            'SYZYASAN',
+            'MEMORY_TOOL_REPLACES_ALLOCATOR',
+            'MEMORY_SANITIZER_INITIAL_SIZE',
+        ],
+      }],
+      ['OS=="win"', {
+        'defines': [
+          '__STD_C',
+          '_CRT_SECURE_NO_DEPRECATE',
+          '_SCL_SECURE_NO_DEPRECATE',
+          # This define is required to pull in the new Win 10 interfaces from
+          # system headers like ShObjIdl.h.
+          'NTDDI_VERSION=0x0A000000',
+          # This is required for ATL to use XP-safe versions of its functions.
+          '_USING_V110_SDK71_',
+        ],
+        'include_dirs': [
+          '<(DEPTH)/third_party/wtl/include',
+        ],
+        'conditions': [
+          ['win_z7!=0', {
+            'msvs_settings': {
+              # Generates debug info when win_z7=1
+              # even if fastbuild=1 (that makes GenerateDebugInformation false).
+              'VCLinkerTool': {
+                'GenerateDebugInformation': 'true',
+              },
+              'VCCLCompilerTool': {
+                'DebugInformationFormat': '1',
+              }
+            }
+          }],  # win_z7!=0
+          ['win_analyze', {
+            'defines!': [
+              # This is prohibited when running /analyze.
+              '_USING_V110_SDK71_',
+            ],
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                # Set WarnAsError to false to disable this setting for most
+                # projects so that compilation continues.
+                'WarnAsError': 'false',
+                # When win_analyze is specified add the /analyze switch.
+                # Also add /WX- to force-disable WarnAsError for projects that
+                # override WarnAsError.
+                # Also, disable various noisy warnings that have low value.
+                'AdditionalOptions': [
+                  '/analyze:WX-',
+                  '/wd6011',  # Dereferencing NULL pointer
+                  '/wd6312',  # Possible infinite loop: use of the constant
+                    # EXCEPTION_CONTINUE_EXECUTION in the exception-filter
+                  '/wd6326',  # Potential comparison of constant with constant
+                  '/wd28159', # Consider using 'GetTickCount64'
+                  '/wd28204', # Inconsistent SAL annotations
+                  '/wd28251', # Inconsistent SAL annotations
+                  '/wd28252', # Inconsistent SAL annotations
+                  '/wd28253', # Inconsistent SAL annotations
+                  '/wd28196', # The precondition is not satisfied
+                  '/wd28301', # Inconsistent SAL annotations
+                  '/wd6340',  # Sign mismatch in function parameter
+                  '/wd28182', # Dereferencing NULL pointer
+                  # C6285 is ~16% of raw warnings and has low value
+                  '/wd6285',  # non-zero constant || non-zero constant
+                  # C6334 is ~80% of raw warnings and has low value
+                  '/wd6334',  # sizeof applied to an expression with an operator
+                ],
+              },
+            },
+          }],  # win_analyze
+        ],
+      }],  # OS==win
+      ['chromecast==1', {
+        'defines': [
+          'LOG_DISABLED=0',
+        ],
+      }],
+      ['enable_task_manager==1', {
+        'defines': [
+          'ENABLE_TASK_MANAGER=1',
+        ],
+      }],
+      ['enable_extensions==1', {
+        'defines': [
+          'ENABLE_EXTENSIONS=1',
+        ],
+      }],
+      ['OS=="win" and branding=="Chrome"', {
+        'defines': ['ENABLE_SWIFTSHADER'],
+      }],
+      ['enable_dart==1', {
+        'defines': ['WEBKIT_USING_DART=1'],
+      }],
+      ['enable_pdf==1', {
+        'defines': ['ENABLE_PDF=1'],
+      }],
+      ['enable_plugin_installation==1', {
+        'defines': ['ENABLE_PLUGIN_INSTALLATION=1'],
+      }],
+      ['enable_plugins==1', {
+        'defines': ['ENABLE_PLUGINS=1'],
+      }],
+      ['enable_session_service==1', {
+        'defines': ['ENABLE_SESSION_SERVICE=1'],
+      }],
+      ['enable_themes==1', {
+        'defines': ['ENABLE_THEMES=1'],
+      }],
+      ['enable_basic_printing==1 or enable_print_preview==1', {
+        # Convenience define for ENABLE_BASIC_PRINTING || ENABLE_PRINT_PREVIEW.
+        'defines': ['ENABLE_PRINTING=1'],
+      }],
+      ['enable_basic_printing==1', {
+        # Enable basic printing support and UI.
+        'defines': ['ENABLE_BASIC_PRINTING=1'],
+      }],
+      ['enable_print_preview==1', {
+        # Enable printing with print preview.
+        # Can be defined without ENABLE_BASIC_PRINTING.
+        'defines': ['ENABLE_PRINT_PREVIEW=1'],
+      }],
+      ['enable_spellcheck==1', {
+        'defines': ['ENABLE_SPELLCHECK=1'],
+      }],
+      ['use_browser_spellchecker', {
+        'defines': ['USE_BROWSER_SPELLCHECKER=1'],
+      }],
+      ['use_minikin_hyphenation', {
+        'defines': ['USE_MINIKIN_HYPHENATION=1'],
+      }],
+      ['enable_captive_portal_detection==1', {
+        'defines': ['ENABLE_CAPTIVE_PORTAL_DETECTION=1'],
+      }],
+      ['enable_app_list==1', {
+        'defines': ['ENABLE_APP_LIST=1'],
+      }],
+      ['disable_file_support==1', {
+        'defines': ['DISABLE_FILE_SUPPORT=1'],
+      }],
+      ['disable_ftp_support==1', {
+        'defines': ['DISABLE_FTP_SUPPORT=1'],
+      }],
+      ['enable_supervised_users==1', {
+        'defines': ['ENABLE_SUPERVISED_USERS=1'],
+      }],
+      ['enable_mdns==1', {
+        'defines': ['ENABLE_MDNS=1'],
+      }],
+      ['enable_service_discovery==1', {
+        'defines' : [ 'ENABLE_SERVICE_DISCOVERY=1' ],
+      }],
+      ['enable_hangout_services_extension==1', {
+        'defines': ['ENABLE_HANGOUT_SERVICES_EXTENSION=1'],
+      }],
+      ['enable_ipc_fuzzer==1', {
+        'defines': ['ENABLE_IPC_FUZZER=1'],
+      }],
+      ['video_hole==1', {
+        'defines': ['VIDEO_HOLE=1'],
+      }],
+      ['v8_use_external_startup_data==1', {
+       'defines': ['V8_USE_EXTERNAL_STARTUP_DATA'],
+      }],
+      ['enable_webvr==1', {
+        'defines': ['ENABLE_WEBVR'],
+      }],
+
+      # SAFE_BROWSING_DB_LOCAL - service manages a local database.
+      # SAFE_BROWSING_DB_REMOTE - service talks via API to a database
+      # SAFE_BROWSING_CSD - enable client-side phishing detection.
+      ['safe_browsing==1', {
+        'defines': [
+          # TODO(nparker): Remove existing uses of FULL_SAFE_BROWSING
+          'FULL_SAFE_BROWSING',
+          'SAFE_BROWSING_CSD',
+          'SAFE_BROWSING_DB_LOCAL',
+        ],
+      }],
+      ['safe_browsing==2 and OS!="ios"', {
+        'defines': [
+          'SAFE_BROWSING_DB_REMOTE',
+        ],
+      }],
+    ],  # conditions for 'target_defaults'
+    'target_conditions': [
+      ['<(use_libpci)==1', {
+        'defines': ['USE_LIBPCI=1'],
+      }],
+      ['<(use_openssl_certs)==1', {
+        'defines': ['USE_OPENSSL_CERTS=1'],
+      }],
+      ['>(nacl_untrusted_build)==1', {
+        'defines': [
+          'USE_OPENSSL_CERTS=1',
+        ],
+      }],
+      ['<(use_glib)==1 and >(nacl_untrusted_build)==0', {
+        'defines': ['USE_GLIB=1'],
+      }],
+      ['<(use_nss_certs)==1 and >(nacl_untrusted_build)==0', {
+        'defines': ['USE_NSS_CERTS=1'],
+      }],
+      ['<(chromeos)==1 and >(nacl_untrusted_build)==0', {
+        'defines': ['OS_CHROMEOS=1'],
+      }],
+      ['<(asan)==1 and >(nacl_untrusted_build)==0', {
+        'defines': [
+          'ADDRESS_SANITIZER',
+          'MEMORY_TOOL_REPLACES_ALLOCATOR',
+          'MEMORY_SANITIZER_INITIAL_SIZE',
+        ],
+      }],
+      ['enable_wexit_time_destructors==1 and OS!="win"', {
+        # TODO: Enable on Windows too, http://crbug.com/404525
+        'variables': { 'clang_warning_flags': ['-Wexit-time-destructors']},
+      }],
+      ['chromium_code==0', {
+        'variables': {
+          'clang_warning_flags': [
+            # Lots of third-party libraries have unused variables. Instead of
+            # suppressing them individually, we just blanket suppress them here.
+            '-Wno-unused-variable',
+          ],
+        },
+        'conditions': [
+          [ 'os_posix==1 and OS!="mac" and OS!="ios"', {
+            # Remove -Wextra for third-party code.
+            'cflags!': [ '-Wextra' ],
+            'cflags_cc': [
+              # Don't warn about hash_map in third-party code.
+              '-Wno-deprecated',
+            ],
+          }],
+          [ 'os_posix==1 and clang!=1 and OS!="mac" and OS!="ios"', {
+            # When we don't control the compiler, don't use -Wall for
+            # third-party code either.
+            'cflags!': [ '-Wall' ],
+          }],
+          # TODO: Fix all warnings on chromeos too.
+          [ 'os_posix==1 and OS!="mac" and OS!="ios" and (clang!=1 or chromeos==1)', {
+            'cflags!': [
+              '-Werror',
+            ],
+          }],
+          [ 'OS=="win"', {
+            'defines': [
+              '_CRT_SECURE_NO_DEPRECATE',
+              '_CRT_NONSTDC_NO_WARNINGS',
+              '_CRT_NONSTDC_NO_DEPRECATE',
+              '_SCL_SECURE_NO_DEPRECATE',
+            ],
+            'msvs_disabled_warnings': [
+              # forcing value to bool 'true' or 'false' (performance warning)
+              4800,
+            ],
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                'WarningLevel': '3',
+                'WarnAsError': 'true',
+                'Detect64BitPortabilityProblems': 'false',
+              },
+            },
+            'conditions': [
+              ['buildtype=="Official"', {
+                'msvs_settings': {
+                  'VCCLCompilerTool': { 'WarnAsError': 'false' },
+                }
+              }],
+              [ 'component=="shared_library"', {
+              # TODO(darin): Unfortunately, some third_party code depends on base.
+                'msvs_disabled_warnings': [
+                  4251,  # class 'std::xx' needs to have dll-interface.
+                 ],
+              }],
+            ],
+          }],
+
+          [ 'OS=="mac" or OS=="ios"', {
+            'xcode_settings': {
+              'WARNING_CFLAGS!': ['-Wextra'],
+            },
+            'conditions': [
+              ['buildtype=="Official"', {
+                'xcode_settings': {
+                  'GCC_TREAT_WARNINGS_AS_ERRORS': 'NO',    # -Werror
+                },
+              }],
+            ],
+          }],
+          [ 'OS=="ios"', {
+            'xcode_settings': {
+              'RUN_CLANG_STATIC_ANALYZER': 'NO',
+              # Several internal ios directories generate numerous warnings for
+              # -Wobjc-missing-property-synthesis.
+              'CLANG_WARN_OBJC_MISSING_PROPERTY_SYNTHESIS': 'NO',
+            },
+          }],
+        ],
+      }, {
+        'includes': [
+           # Rules for excluding e.g. foo_win.cc from the build on non-Windows.
+          'filename_rules.gypi',
+        ],
+        # In Chromium code, we define __STDC_foo_MACROS in order to get the
+        # C99 macros on Mac and Linux.
+        'defines': [
+          '__STDC_CONSTANT_MACROS',
+          '__STDC_FORMAT_MACROS',
+        ],
+        'conditions': [
+          ['OS=="win"', {
+            # turn on warnings for signed/unsigned mismatch on chromium code.
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': ['/we4389'],
+              },
+            },
+          }],
+          ['OS=="win" and component=="shared_library"', {
+            'msvs_disabled_warnings': [
+              4251,  # class 'std::xx' needs to have dll-interface.
+            ],
+          }],
+        ],
+      }],
+    ],  # target_conditions for 'target_defaults'
+    'default_configuration': 'Debug',
+    'configurations': {
+      # VCLinkerTool LinkIncremental values below:
+      #   0 == default
+      #   1 == /INCREMENTAL:NO
+      #   2 == /INCREMENTAL
+      # Debug links incremental, Release does not.
+      #
+      # Abstract base configurations to cover common attributes.
+      #
+      'Common_Base': {
+        'abstract': 1,
+        'msvs_configuration_attributes': {
+          'OutputDirectory': '<(DEPTH)\\build\\<(build_dir_prefix)$(ConfigurationName)',
+          'IntermediateDirectory': '$(OutDir)\\obj\\$(ProjectName)',
+          'CharacterSet': '1',
+        },
+        'msvs_settings':{
+          'VCCLCompilerTool': {
+            'AdditionalOptions': [
+              '/bigobj',
+              # Tell the compiler to crash on failures. This is undocumented
+              # and unsupported but very handy.
+              '/d2FastFail',
+            ],
+          },
+          'VCLinkerTool': {
+            # Add the default import libs.
+            'AdditionalDependencies': [
+              'kernel32.lib',
+              'gdi32.lib',
+              'winspool.lib',
+              'comdlg32.lib',
+              'advapi32.lib',
+              'shell32.lib',
+              'ole32.lib',
+              'oleaut32.lib',
+              'user32.lib',
+              'uuid.lib',
+              'odbc32.lib',
+              'odbccp32.lib',
+              'delayimp.lib',
+              'credui.lib',
+            ],
+            'AdditionalOptions': [
+              # Suggested by Microsoft Devrel to avoid
+              #   LINK : fatal error LNK1248: image size (80000000) exceeds maximum allowable size (80000000)
+              # which started happening more regularly after VS2013 Update 4.
+              # Needs to be a bit lower for VS2015, or else errors out.
+              '/maxilksize:0x7ff00000',
+              # Tell the linker to crash on failures.
+              '/fastfail',
+            ],
+          },
+        },
+        'conditions': [
+          ['OS=="win" and win_fastlink==1 and MSVS_VERSION != "2013"', {
+            'msvs_settings': {
+              'VCLinkerTool': {
+                # /PROFILE is incompatible with /debug:fastlink
+                'Profile': 'false',
+                'AdditionalOptions': [
+                  # Tell VS 2015+ to create a PDB that references debug
+                  # information in .obj and .lib files instead of copying
+                  # it all.
+                  '/DEBUG:FASTLINK',
+                ],
+              },
+            },
+          }],
+          ['OS=="win" and MSVS_VERSION == "2015"', {
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  # Work around crbug.com/526851, bug in VS 2015 RTM compiler.
+                  '/Zc:sizedDealloc-',
+                  # Disable thread-safe statics to avoid overhead and because
+                  # they are disabled on other platforms. See crbug.com/587210
+                  # and -fno-threadsafe-statics.
+                  '/Zc:threadSafeInit-',
+                ],
+              },
+            },
+          }],
+        ],
+      },
+      'x86_Base': {
+        'abstract': 1,
+        'msvs_settings': {
+          'VCLinkerTool': {
+            'MinimumRequiredVersion': '5.01',  # XP.
+            'TargetMachine': '1',
+          },
+          'VCLibrarianTool': {
+            'TargetMachine': '1',
+          },
+        },
+        'msvs_configuration_platform': 'Win32',
+      },
+      'x64_Base': {
+        'abstract': 1,
+        'msvs_configuration_platform': 'x64',
+        'msvs_settings': {
+          'VCLinkerTool': {
+            # Make sure to understand http://crbug.com/361720 if you want to
+            # increase this.
+            'MinimumRequiredVersion': '5.02',  # Server 2003.
+            'TargetMachine': '17', # x86 - 64
+            'AdditionalLibraryDirectories!':
+              ['<(windows_sdk_path)/Lib/10.0.10586.0/um/x86'],
+            'AdditionalLibraryDirectories':
+              ['<(windows_sdk_path)/Lib/10.0.10586.0/um/x64'],
+            # Doesn't exist x64 SDK. Should use oleaut32 in any case.
+            'IgnoreDefaultLibraryNames': [ 'olepro32.lib' ],
+          },
+          'VCLibrarianTool': {
+            'AdditionalLibraryDirectories!':
+              ['<(windows_sdk_path)/Lib/10.0.10586.0/um/x86'],
+            'AdditionalLibraryDirectories':
+              ['<(windows_sdk_path)/Lib/10.0.10586.0/um/x64'],
+            'TargetMachine': '17', # x64
+          },
+        },
+      },
+      'Debug_Base': {
+        'abstract': 1,
+        'defines': [
+          'DYNAMIC_ANNOTATIONS_ENABLED=1',
+          'WTF_USE_DYNAMIC_ANNOTATIONS=1',
+        ],
+        'xcode_settings': {
+          'GCC_OPTIMIZATION_LEVEL': '<(mac_debug_optimization)',
+          'OTHER_CFLAGS': [
+            '<@(debug_extra_cflags)',
+          ],
+        },
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'Optimization': '<(win_debug_Optimization)',
+            'PreprocessorDefinitions': ['_DEBUG'],
+            'BasicRuntimeChecks': '<(win_debug_RuntimeChecks)',
+            'RuntimeLibrary': '<(win_debug_RuntimeLibrary)',
+            'conditions': [
+              # According to MSVS, InlineFunctionExpansion=0 means
+              # "default inlining", not "/Ob0".
+              # Thus, we have to handle InlineFunctionExpansion==0 separately.
+              ['win_debug_InlineFunctionExpansion==0', {
+                'AdditionalOptions': ['/Ob0'],
+              }],
+              ['win_debug_InlineFunctionExpansion!=""', {
+                'InlineFunctionExpansion':
+                  '<(win_debug_InlineFunctionExpansion)',
+              }],
+              ['win_debug_disable_iterator_debugging==1', {
+                'PreprocessorDefinitions': ['_HAS_ITERATOR_DEBUGGING=0'],
+              }],
+
+              # if win_debug_OmitFramePointers is blank, leave as default
+              ['win_debug_OmitFramePointers==1', {
+                'OmitFramePointers': 'true',
+              }],
+              ['win_debug_OmitFramePointers==0', {
+                'OmitFramePointers': 'false',
+                # The above is not sufficient (http://crbug.com/106711): it
+                # simply eliminates an explicit "/Oy", but both /O2 and /Ox
+                # perform FPO regardless, so we must explicitly disable.
+                # We still want the false setting above to avoid having
+                # "/Oy /Oy-" and warnings about overriding.
+                'AdditionalOptions': ['/Oy-'],
+              }],
+            ],
+            'AdditionalOptions': [ '<@(win_debug_extra_cflags)', ],
+          },
+          'VCLinkerTool': {
+            'LinkIncremental': '<(msvs_debug_link_incremental)',
+            # ASLR makes debugging with windbg difficult because Chrome.exe and
+            # Chrome.dll share the same base name. As result, windbg will
+            # name the Chrome.dll module like chrome_<base address>, where
+            # <base address> typically changes with each launch. This in turn
+            # means that breakpoints in Chrome.dll don't stick from one launch
+            # to the next. For this reason, we turn ASLR off in debug builds.
+            # Note that this is a three-way bool, where 0 means to pick up
+            # the default setting, 1 is off and 2 is on.
+            'RandomizedBaseAddress': 1,
+          },
+          'VCResourceCompilerTool': {
+            'PreprocessorDefinitions': ['_DEBUG'],
+          },
+        },
+        'variables': {
+          'clang_warning_flags': [
+            # Allow comparing the address of references and 'this' against 0
+            # in debug builds. Technically, these can never be null in
+            # well-defined C/C++ and Clang can optimize such checks away in
+            # release builds, but they may be used in asserts in debug builds.
+            '-Wno-undefined-bool-conversion',
+            '-Wno-tautological-undefined-compare',
+          ],
+        },
+        'conditions': [
+          ['OS=="linux" or OS=="android"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '<@(debug_extra_cflags)',
+                ],
+              }],
+            ],
+          }],
+          ['OS=="linux" and target_arch!="ia32" and disable_glibcxx_debug==0', {
+            # Enable libstdc++ debugging facilities to help catch problems
+            # early, see http://crbug.com/65151 .
+            # TODO(phajdan.jr): Should we enable this for all of POSIX?
+            'defines': ['_GLIBCXX_DEBUG=1',],
+          }],
+          ['release_valgrind_build==0', {
+            'xcode_settings': {
+              'OTHER_CFLAGS': [
+                '-fstack-protector-strong',  # Implies -fstack-protector
+              ],
+            },
+          }],
+        ],
+      },
+      'Release_Base': {
+        'abstract': 1,
+        'defines': [
+          'NDEBUG',
+        ],
+        'xcode_settings': {
+          'DEAD_CODE_STRIPPING': 'YES',  # -Wl,-dead_strip
+          'GCC_OPTIMIZATION_LEVEL': '<(mac_release_optimization)',
+          'OTHER_CFLAGS': [ '<@(release_extra_cflags)', ],
+        },
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'RuntimeLibrary': '<(win_release_RuntimeLibrary)',
+            'conditions': [
+              # In official builds, each target will self-select
+              # an optimization level.
+              ['buildtype!="Official"', {
+                  'Optimization': '<(win_release_Optimization)',
+                },
+              ],
+              # According to MSVS, InlineFunctionExpansion=0 means
+              # "default inlining", not "/Ob0".
+              # Thus, we have to handle InlineFunctionExpansion==0 separately.
+              ['win_release_InlineFunctionExpansion==0', {
+                'AdditionalOptions': ['/Ob0'],
+              }],
+              ['win_release_InlineFunctionExpansion!=""', {
+                'InlineFunctionExpansion':
+                  '<(win_release_InlineFunctionExpansion)',
+              }],
+
+              # if win_release_OmitFramePointers is blank, leave as default
+              ['win_release_OmitFramePointers==1', {
+                'OmitFramePointers': 'true',
+              }],
+              ['win_release_OmitFramePointers==0', {
+                'OmitFramePointers': 'false',
+                # The above is not sufficient (http://crbug.com/106711): it
+                # simply eliminates an explicit "/Oy", but both /O2 and /Ox
+                # perform FPO regardless, so we must explicitly disable.
+                # We still want the false setting above to avoid having
+                # "/Oy /Oy-" and warnings about overriding.
+                'AdditionalOptions': ['/Oy-'],
+              }],
+              ['asan==0', {
+                # Put data in separate COMDATs. This allows the linker
+                # to put bit-identical constants at the same address even if
+                # they're unrelated constants, which saves binary size.
+                # This optimization can't be used when ASan is enabled because
+                # it is not compatible with the ASan ODR checker.
+                'AdditionalOptions': ['/Gw'],
+              }],
+            ],
+            'AdditionalOptions': [
+                '/d2Zi+',  # Improve debugging of Release builds.
+                '/Zc:inline',  # Remove unreferenced COMDAT (faster links).
+                '<@(win_release_extra_cflags)',
+            ],
+          },
+          'VCLinkerTool': {
+            # LinkIncremental is a tri-state boolean, where 0 means default
+            # (i.e., inherit from parent solution), 1 means false, and
+            # 2 means true.
+            'LinkIncremental': '1',
+            # This corresponds to the /PROFILE flag which ensures the PDB
+            # file contains FIXUP information (growing the PDB file by about
+            # 5%) but does not otherwise alter the output binary. This
+            # information is used by the Syzygy optimization tool when
+            # decomposing the release image.
+            'Profile': 'true',
+          },
+        },
+        'conditions': [
+          ['msvs_use_common_release', {
+            'includes': ['release.gypi'],
+          }],
+          ['release_valgrind_build==0 and tsan==0', {
+            'defines': [
+              'NVALGRIND',
+              'DYNAMIC_ANNOTATIONS_ENABLED=0',
+            ],
+          }, {
+            'defines': [
+              'MEMORY_TOOL_REPLACES_ALLOCATOR',
+              'MEMORY_SANITIZER_INITIAL_SIZE',
+              'DYNAMIC_ANNOTATIONS_ENABLED=1',
+              'WTF_USE_DYNAMIC_ANNOTATIONS=1',
+            ],
+          }],
+          ['OS=="win" and win_use_allocator_shim==1', {
+            'defines': [
+              'ALLOCATOR_SHIM'
+            ],
+          }],
+          # _FORTIFY_SOURCE isn't really supported by Clang now, see
+          # http://llvm.org/bugs/show_bug.cgi?id=16821.
+          # It seems to work fine with Ubuntu 12 headers though, so use it
+          # in official builds.
+          ['os_posix==1 and (asan!=1 and msan!=1 and tsan!=1 and lsan!=1 and ubsan!=1) and (OS!="linux" or clang!=1 or buildtype=="Official")', {
+            'target_conditions': [
+              ['chromium_code==1', {
+                # Non-chromium code is not guaranteed to compile cleanly
+                # with _FORTIFY_SOURCE. Also, fortified build may fail
+                # when optimizations are disabled, so only do that for Release
+                # build.
+                'defines': [
+                  '_FORTIFY_SOURCE=2',
+                ],
+              }],
+            ],
+          }],
+          ['OS=="linux" or OS=="android"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '<@(release_extra_cflags)',
+                ],
+                'conditions': [
+                  ['enable_resource_whitelist_generation==1', {
+                    'cflags': [
+                      '-Wunknown-pragmas -Wno-error=unknown-pragmas',
+                    ],
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['OS=="ios"', {
+            'defines': [
+              'NS_BLOCK_ASSERTIONS=1',
+            ],
+          }],
+        ],
+      },
+      #
+      # Concrete configurations
+      #
+      'Debug': {
+        'inherit_from': ['Common_Base', 'x86_Base', 'Debug_Base'],
+      },
+      'Release': {
+        'inherit_from': ['Common_Base', 'x86_Base', 'Release_Base'],
+      },
+      'conditions': [
+        [ 'OS=="ios"', {
+          'Profile': {
+            'inherit_from': ['Common_Base', 'x86_Base', 'Release_Base'],
+            'target_conditions': [
+              [ '_type=="executable"', {
+                # To get a real .dSYM bundle produced by dsymutil, set the
+                # debug information format to dwarf-with-dsym.  Since
+                # strip_from_xcode will not be used, set Xcode to do the
+                # stripping as well.
+                'xcode_settings': {
+                  'DEBUG_INFORMATION_FORMAT': 'dwarf-with-dsym',
+                  'DEPLOYMENT_POSTPROCESSING': 'YES',
+                  'STRIP_INSTALLED_PRODUCT': 'YES',
+                },
+              }],
+            ],
+          },
+        }],
+        [ 'OS=="win"', {
+          # TODO(bradnelson): add a gyp mechanism to make this more graceful.
+          'Debug_x64': {
+            'inherit_from': ['Common_Base', 'x64_Base', 'Debug_Base'],
+          },
+          'Release_x64': {
+            'inherit_from': ['Common_Base', 'x64_Base', 'Release_Base'],
+          },
+        }],
+      ],
+    },
+  },
+  'conditions': [
+    ['os_posix==1', {
+      'target_defaults': {
+        'ldflags': [
+          '-Wl,-z,now',
+          '-Wl,-z,relro',
+        ],
+        # TODO(glider): enable the default options on other systems.
+        'conditions': [
+          ['use_sanitizer_options==1 and ((OS=="linux" and (chromeos==0 or target_arch!="ia32")) or OS=="mac")', {
+            'dependencies': [
+              '<(DEPTH)/build/sanitizers/sanitizers.gyp:sanitizer_options',
+            ],
+          }],
+        ],
+      },
+    }],
+    # TODO(jochen): Enable this on chromeos on arm. http://crbug.com/356580
+    ['os_posix==1 and disable_fatal_linker_warnings==0 and use_evdev_gestures==0 and (chromeos==0 or target_arch!="arm")', {
+      'target_defaults': {
+        'ldflags': [
+          '-Wl,--fatal-warnings',
+        ],
+      },
+    }],
+    # -Wl,-z,-defs doesn't work with the sanitiziers, http://crbug.com/452065
+    ['(OS=="linux" or OS=="android") and asan==0 and msan==0 and tsan==0 and ubsan==0 and ubsan_security==0 and ubsan_vptr==0 and cfi_diag==0', {
+      'target_defaults': {
+        'ldflags': [
+          '-Wl,-z,defs',
+        ],
+      },
+    }],
+    ['os_posix==1 and chromeos==0', {
+      # Chrome OS enables -fstack-protector-strong via its build wrapper,
+      # and we want to avoid overriding this, so stack-protector is only
+      # enabled when not building on Chrome OS.
+      # TODO(phajdan.jr): Use -fstack-protector-strong when our gcc
+      # supports it.  See also https://crbug.com/533294
+      'target_defaults': {
+        'cflags': [
+          '-fstack-protector',
+          '--param=ssp-buffer-size=4',
+        ],
+      },
+    }],
+    ['os_posix==1 and OS=="linux"', {
+      'defines': [
+        '_LARGEFILE_SOURCE',
+        '_LARGEFILE64_SOURCE',
+        '_FILE_OFFSET_BITS=64',
+      ],
+    }],
+    ['os_posix==1 and OS!="mac" and OS!="ios"', {
+      'target_defaults': {
+        # Enable -Werror by default, but put it in a variable so it can
+        # be disabled in ~/.gyp/include.gypi on the valgrind builders.
+        'variables': {
+          'werror%': '-Werror',
+          'libraries_for_target%': '',
+          'conditions' : [
+            # Enable -Wextra for chromium_code when we control the compiler.
+            ['clang==1', { 'wextra': '-Wextra' }, { 'wextra': '-Wno-extra' }],
+          ],
+        },
+        'defines': [
+          '_FILE_OFFSET_BITS=64',
+        ],
+        'cflags': [
+          '<(werror)',  # See note above about the werror variable.
+          '-pthread',
+          '-fno-strict-aliasing',  # See http://crbug.com/32204
+          '-Wall',
+          '<(wextra)',
+          # Don't warn about unused function params.  We use those everywhere.
+          '-Wno-unused-parameter',
+          # Don't warn about the "struct foo f = {0};" initialization pattern.
+          '-Wno-missing-field-initializers',
+          # Don't export any symbols (for example, to plugins we dlopen()).
+          # Note: this is *required* to make some plugins work.
+          '-fvisibility=hidden',
+          '-pipe',
+        ],
+        'cflags_cc': [
+          '-fno-exceptions',
+          '-fno-rtti',
+          # If this is removed then remove the corresponding /Zc:threadSafeInit-
+          # for Windows.
+          '-fno-threadsafe-statics',
+          # Make inline functions have hidden visiblity by default.
+          # Surprisingly, not covered by -fvisibility=hidden.
+          '-fvisibility-inlines-hidden',
+        ],
+        'ldflags': [
+          '-pthread', '-Wl,-z,noexecstack',
+        ],
+        'libraries' : [
+          '<(libraries_for_target)',
+        ],
+        'configurations': {
+          'Debug_Base': {
+            'variables': {
+              'debug_optimize%': '0',
+            },
+            'defines': [
+              '_DEBUG',
+            ],
+            'cflags': [
+              '-O>(debug_optimize)',
+              '-g',
+            ],
+            'conditions' : [
+              ['OS=="android" and target_arch!="mipsel" and target_arch!="mips64el"', {
+                # TODO(jdduke) Re-enable on mips after resolving linking
+                # issues with libc++ (crbug.com/456380).
+                'ldflags': [
+                  # Warn in case of text relocations.
+                  '-Wl,--warn-shared-textrel',
+                ],
+              }],
+              ['OS=="android" and android_full_debug==0', {
+                # Some configurations are copied from Release_Base to reduce
+                # the binary size.
+                'variables': {
+                  'debug_optimize%': 's',
+                },
+                'cflags': [
+                  '-fdata-sections',
+                  '-ffunction-sections',
+                ],
+                'ldflags': [
+                  '-Wl,-O1',
+                  '-Wl,--as-needed',
+                ],
+              }],
+              ['OS=="android" and android_full_debug==0 and target_arch!="arm64"', {
+                # We don't omit frame pointers on arm64 since they are required
+                # to correctly unwind stackframes which contain system library
+                # function frames (crbug.com/391706).
+                'cflags': [
+                  '-fomit-frame-pointer',
+                ],
+              }],
+              ['OS=="linux" and target_arch=="ia32"', {
+                'ldflags': [
+                  '-Wl,--no-as-needed',
+                ],
+              }],
+              ['debug_unwind_tables==1', {
+                'cflags': ['-funwind-tables'],
+              }, {
+                'cflags': ['-fno-unwind-tables', '-fno-asynchronous-unwind-tables'],
+                'defines': ['NO_UNWIND_TABLES'],
+              }],
+              ['linux_use_debug_fission==1 and linux_use_gold_flags==1 and binutils_version>=223', {
+                'cflags': ['-gsplit-dwarf'],
+              }],
+            ],
+          },
+          'Release_Base': {
+            'variables': {
+              'release_optimize%': '2',
+              # Binaries become big and gold is unable to perform GC
+              # and remove unused sections for some of test targets
+              # on 32 bit platform.
+              # (This is currently observed only in chromeos valgrind bots)
+              # The following flag is to disable --gc-sections linker
+              # option for these bots.
+              'no_gc_sections%': 0,
+
+              # TODO(bradnelson): reexamine how this is done if we change the
+              # expansion of configurations
+              'release_valgrind_build%': 0,
+            },
+            'cflags': [
+              '-O<(release_optimize)',
+              # Don't emit the GCC version ident directives, they just end up
+              # in the .comment section taking up binary size.
+              '-fno-ident',
+              # Put data and code in their own sections, so that unused symbols
+              # can be removed at link time with --gc-sections.
+              '-fdata-sections',
+              '-ffunction-sections',
+            ],
+            'ldflags': [
+              # Specifically tell the linker to perform optimizations.
+              # See http://lwn.net/Articles/192624/ .
+              '-Wl,-O1',
+              '-Wl,--as-needed',
+            ],
+            'conditions' : [
+              ['no_gc_sections==0', {
+                'ldflags': [
+                  '-Wl,--gc-sections',
+                ],
+              }],
+              ['OS=="android" and target_arch!="arm64"', {
+                # We don't omit frame pointers on arm64 since they are required
+                # to correctly unwind stackframes which contain system library
+                # function frames (crbug.com/391706).
+                'cflags': [
+                  '-fomit-frame-pointer',
+                ]
+              }],
+              ['OS=="android" and target_arch!="mipsel" and target_arch!="mips64el"', {
+                # TODO(jdduke) Re-enable on mips after resolving linking
+                # issues with libc++ (crbug.com/456380).
+                'ldflags': [
+                  # Warn in case of text relocations.
+                  '-Wl,--warn-shared-textrel',
+                ],
+              }],
+              ['OS=="android"', {
+                'variables': {
+                  'release_optimize%': 's',
+                },
+              }, {
+                'ldflags': [
+                  # TODO(pcc): Fix linker bug which requires us to link pthread
+                  # unconditionally here (crbug.com/623236).
+                  '-Wl,--no-as-needed',
+                  '-lpthread',
+                  '-Wl,--as-needed',
+                ],
+              }],
+              ['profiling==1', {
+                'cflags': [
+                  '-fno-omit-frame-pointer',
+                  '-g',
+                ],
+                'conditions' : [
+                  ['profiling_full_stack_frames==1', {
+                    'cflags': [
+                      '-fno-inline',
+                      '-fno-optimize-sibling-calls',
+                    ],
+                  }],
+                ],
+              }],
+              ['release_unwind_tables==1', {
+                'cflags': ['-funwind-tables'],
+              }, {
+                'cflags': ['-fno-unwind-tables', '-fno-asynchronous-unwind-tables'],
+                'defines': ['NO_UNWIND_TABLES'],
+              }],
+            ],
+          },
+        },
+        'conditions': [
+          ['target_arch=="ia32"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'asflags': [
+                  # Needed so that libs with .s files (e.g. libicudata.a)
+                  # are compatible with the general 32-bit-ness.
+                  '-32',
+                ],
+                # All floating-point computations on x87 happens in 80-bit
+                # precision.  Because the C and C++ language standards allow
+                # the compiler to keep the floating-point values in higher
+                # precision than what's specified in the source and doing so
+                # is more efficient than constantly rounding up to 64-bit or
+                # 32-bit precision as specified in the source, the compiler,
+                # especially in the optimized mode, tries very hard to keep
+                # values in x87 floating-point stack (in 80-bit precision)
+                # as long as possible. This has important side effects, that
+                # the real value used in computation may change depending on
+                # how the compiler did the optimization - that is, the value
+                # kept in 80-bit is different than the value rounded down to
+                # 64-bit or 32-bit. There are possible compiler options to
+                # make this behavior consistent (e.g. -ffloat-store would keep
+                # all floating-values in the memory, thus force them to be
+                # rounded to its original precision) but they have significant
+                # runtime performance penalty.
+                #
+                # -mfpmath=sse -msse2 makes the compiler use SSE instructions
+                # which keep floating-point values in SSE registers in its
+                # native precision (32-bit for single precision, and 64-bit
+                # for double precision values). This means the floating-point
+                # value used during computation does not change depending on
+                # how the compiler optimized the code, since the value is
+                # always kept in its specified precision.
+                #
+                # Refer to http://crbug.com/348761 for rationale behind SSE2
+                # being a minimum requirement for 32-bit Linux builds and
+                # http://crbug.com/313032 for an example where this has "bit"
+                # us in the past.
+                'cflags': [
+                  '-msse2',
+                  '-mfpmath=sse',
+                  '-mmmx',  # Allows mmintrin.h for MMX intrinsics.
+                  '-m32',
+                ],
+                'ldflags': [
+                  '-m32',
+                ],
+                'conditions': [
+                  # Use gold linker for Android ia32 target.
+                  ['OS=="android"', {
+                     # Use gold linker for Android ia32 target.
+                    'ldflags': [
+                      '-fuse-ld=gold',
+                    ],
+                    # Use -mstackrealign due to a bug on ia32 Jelly Bean.
+                    # See crbug.com/521527
+                    'cflags': [
+                      '-mstackrealign',
+                    ],
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['target_arch=="x64"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  # Use gold linker for Android x64 target.
+                  ['OS=="android"', {
+                    'ldflags': [
+                      '-fuse-ld=gold',
+                    ],
+                  }],
+                ],
+                'cflags': [
+                  '-m64',
+                  '-march=x86-64',
+                ],
+                'ldflags': [
+                  '-m64',
+                ],
+              }],
+            ],
+          }],
+          ['target_arch=="arm"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  ['clang==0', {
+                    'cflags': [
+                      # Don't warn about "maybe" uninitialized. Clang doesn't
+                      # include this in -Wall but gcc does, and it gives false
+                      # positives.
+                      '-Wno-maybe-uninitialized',
+                    ],
+                    'cflags_cc': [
+                      # The codesourcery arm-2009q3 toolchain warns at that the ABI
+                      # has changed whenever it encounters a varargs function. This
+                      # silences those warnings, as they are not helpful and
+                      # clutter legitimate warnings.
+                      '-Wno-abi',
+                    ],
+                  }],
+                  ['clang==1 and arm_arch!="" and OS!="android"', {
+                    'cflags': [
+                      '-target arm-linux-gnueabihf',
+                    ],
+                    'ldflags': [
+                      '-target arm-linux-gnueabihf',
+                    ],
+                  }],
+                  ['arm_arch!=""', {
+                    'cflags': [
+                      '-march=<(arm_arch)',
+                    ],
+                    'conditions': [
+                      ['use_lto==1 or use_lto_o2==1', {
+                        'ldflags': [
+                          '-march=<(arm_arch)',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['arm_tune!=""', {
+                    'cflags': [
+                      '-mtune=<(arm_tune)',
+                    ],
+                    'conditions': [
+                      ['use_lto==1 or use_lto_o2==1', {
+                        'ldflags': [
+                          '-mtune=<(arm_tune)',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['arm_fpu!=""', {
+                    'cflags': [
+                      '-mfpu=<(arm_fpu)',
+                    ],
+                    'conditions': [
+                      ['use_lto==1 or use_lto_o2==1', {
+                        'ldflags': [
+                          '-mfpu=<(arm_fpu)',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['arm_float_abi!=""', {
+                    'cflags': [
+                      '-mfloat-abi=<(arm_float_abi)',
+                    ],
+                    'conditions': [
+                      ['use_lto==1 or use_lto_o2==1', {
+                        'ldflags': [
+                          '-mfloat-abi=<(arm_float_abi)',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['arm_thumb==1', {
+                    'cflags': [
+                      '-mthumb',
+                    ],
+                    'conditions': [
+                      ['use_lto==1 or use_lto_o2==1', {
+                        'ldflags': [
+                          '-mthumb',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['OS=="android"', {
+                    # Most of the following flags are derived from what Android
+                    # uses by default when building for arm, reference for which
+                    # can be found in the following file in the Android NDK:
+                    # toolchains/arm-linux-androideabi-4.9/setup.mk
+                    'cflags': [
+                      # The tree-sra optimization (scalar replacement for
+                      # aggregates enabling subsequent optimizations) leads to
+                      # invalid code generation when using the Android NDK's
+                      # compiler (r5-r7). This can be verified using
+                      # webkit_unit_tests' WTF.Checked_int8_t test.
+                      '-fno-tree-sra',
+                      # The following option is disabled to improve binary
+                      # size and performance in gcc 4.9.
+                      '-fno-caller-saves',
+                      '-Wno-psabi',
+                    ],
+                    # Android now supports .relro sections properly.
+                    # NOTE: While these flags enable the generation of .relro
+                    # sections, the generated libraries can still be loaded on
+                    # older Android platform versions.
+                    'ldflags': [
+                        '-Wl,-z,relro',
+                        '-Wl,-z,now',
+                        '-fuse-ld=gold',
+                    ],
+                    'conditions': [
+                      ['arm_thumb==1', {
+                        'cflags': [ '-mthumb-interwork' ],
+                      }],
+                      ['profiling==1', {
+                        'cflags': [
+                          # Thumb code with frame pointer makes chrome crash
+                          # early.
+                          '-marm',
+                          '-mapcs-frame', # Required by -fno-omit-frame-pointer.
+                          # The perf report sometimes incorrectly attributes
+                          # code from tail calls.
+                          '-fno-optimize-sibling-calls',
+                        ],
+                        'cflags!': [
+                          '-fomit-frame-pointer',
+                        ],
+                      }],
+                      ['clang==1', {
+                        'cflags!': [
+                          # Clang does not support the following options.
+                          '-mapcs-frame',
+                          '-mthumb-interwork',
+                          '-finline-limit=64',
+                          '-fno-tree-sra',
+                          '-fno-caller-saves',
+                          '-Wno-psabi',
+                        ],
+                      }],
+                      ['clang==1 and linux_use_bundled_gold==0', {
+                        'ldflags': [
+                          # Let clang find the ld.gold in the NDK.
+                          '--gcc-toolchain=<(android_toolchain)/..',
+                        ],
+                      }],
+                      ['asan==1', {
+                        'cflags': [
+                          '-marm', # Required for frame pointer based stack traces.
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['chromecast==1', {
+                    'cflags': [
+                      # We set arm_arch to "" so that -march compiler option
+                      # is not set.  Otherwise a gcc bug that would complain
+                      # about it conflicting with '-mcpu=cortex-a9'. The flag
+                      # '-march=armv7-a' is actually redundant anyway because
+                      # it is enabled by default when we built the toolchain.
+                      # And using '-mcpu=cortex-a9' should be sufficient.
+                      '-mcpu=cortex-a9',
+                      '-funwind-tables',
+                      # Breakpad requires symbols with debugging information
+                      '-g',
+                    ],
+                    'ldflags': [
+                      # We want to statically link libstdc++/libgcc.
+                      '-static-libstdc++',
+                      '-static-libgcc',
+                      # Don't allow visible symbols from libraries that contain
+                      # assembly code with symbols that aren't hidden properly.
+                      # http://b/26390825
+                      '-Wl,--exclude-libs=libffmpeg.a',
+                    ],
+                    'cflags!': [
+                      # Some components in Chromium (e.g. v8, skia, ffmpeg)
+                      # define their own cflags for arm builds that could
+                      # conflict with the flags we set here (e.g.
+                      # '-mcpu=cortex-a9'). Remove these flags explicitly.
+                      '-march=armv7-a',
+                      '-mtune=cortex-a8',
+                    ],
+                    'target_conditions': [
+                      [ '_type=="executable" and OS!="android"', {
+                        # Statically link whole libstdc++ and libgcc in
+                        # executables to ensure only one copy at runtime.
+                        'ldflags': [
+                          # Note executables also get -static-stdlibc++/libgcc.
+                          # Despite including libstdc++/libgcc archives, we
+                          # still need to specify static linking for them in
+                          # order to prevent the executable from having a
+                          # dynamic dependency on them.
+
+                          # Export stdlibc++ and libgcc symbols to force shlibs
+                          # to refer to these symbols from the executable.
+                          '-Wl,--export-dynamic',
+
+                          '-lm', # stdlibc++ requires math.h
+
+                          # In case we redefined stdlibc++ symbols
+                          # (e.g. tc_malloc)
+                          '-Wl,--allow-multiple-definition',
+
+                          '-Wl,--whole-archive',
+                          '-l:libstdc++.a',
+                          '-l:libgcc.a',
+                          '-Wl,--no-whole-archive',
+                        ],
+                      }]
+                    ],
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['target_arch=="arm64"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  ['OS=="android"', {
+                    'cflags!': [
+                       '-fstack-protector',  # stack protector is always enabled on arm64.
+                    ],
+                  }],
+                  ['clang==1 and arm_arch!="" and OS!="android"', {
+                    'cflags': [
+                      '-target aarch64-linux-gnu',
+                     ],
+                     'ldflags': [
+                       '-target aarch64-linux-gnu',
+                     ],
+                 }],
+                ],
+              }],
+            ],
+          }],
+          ['target_arch=="mipsel"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  ['mips_arch_variant=="r6"', {
+                    'conditions': [
+                      ['clang==1', {
+                        'conditions': [
+                          ['OS=="android"', {
+                            'cflags': [ '-target mipsel-linux-android', '-march=mipsel', '-mcpu=mips32r6', ],
+                            'ldflags': [ '-target mipsel-linux-android', ],
+                          }],
+                        ],
+                      }, { # clang==0
+                        'cflags': ['-mips32r6', '-Wa,-mips32r6', ],
+                      }],
+                      ['clang==0 and OS=="android"', {
+                        'ldflags': ['-mips32r6', '-Wl,-melf32ltsmip',],
+                      }],
+                      ['mips_msa==1', {
+                        'cflags': ['-mmsa', '-mfp64', '-msched-weight', '-mload-store-pairs'],
+                      }],
+                    ],
+                    'cflags': [ '-mfp64', '-mno-odd-spreg' ],
+                    'ldflags': [ '-mfp64', '-mno-odd-spreg' ],
+                  }],
+                  ['mips_arch_variant=="r2"', {
+                    'conditions': [
+                      ['mips_float_abi=="hard" and mips_fpu_mode!=""', {
+                        'cflags': ['-m<(mips_fpu_mode)'],
+                      }],
+                      ['clang==1', {
+                         'conditions': [
+                          ['OS=="android"', {
+                            'cflags': [ '-target mipsel-linux-android', '-march=mipsel', '-mcpu=mips32r2'],
+                            'ldflags': [ '-target mipsel-linux-android', ],
+                          }, {
+                            'cflags': [ '-target mipsel-linux-gnu', '-march=mipsel', '-mcpu=mips32r2'],
+                            'ldflags': [ '-target mipsel-linux-gnu', ],
+                          }],
+                         ],
+                      }, { # clang==0
+                        'cflags': ['-mips32r2', '-Wa,-mips32r2', ],
+                      }],
+                    ],
+                  }],
+                  ['mips_arch_variant=="r1"', {
+                    'conditions': [
+                      ['clang==1', {
+                        'conditions': [
+                          ['OS=="android"', {
+                            'cflags': [ '-target mipsel-linux-android', '-march=mipsel', '-mcpu=mips32'],
+                            'ldflags': [ '-target mipsel-linux-android', ],
+                          }, {
+                            'cflags': [ '-target mipsel-linux-gnu', '-march=mipsel', '-mcpu=mips32'],
+                            'ldflags': [ '-target mipsel-linux-gnu', ],
+                          }],
+                        ],
+                      }, { # clang==0
+                        'cflags': ['-mips32', '-Wa,-mips32', ],
+                      }],
+                    ],
+                  }],
+                  ['clang==1', {
+                    'cflags!': [
+                      # Clang does not support the following options.
+                      '-finline-limit=64',
+                    ],
+                    # TODO(gordanac) Enable integrated-as.
+                    'cflags': [ '-fno-integrated-as' ],
+                    'conditions': [
+                      ['OS=="android"', {
+                        'cflags': [
+                          # Else /usr/bin/as gets picked up.
+                          '-B<(android_toolchain)',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['clang==1 and OS=="android"', {
+                    'ldflags': [
+                      # Let clang find the ld in the NDK.
+                      '--gcc-toolchain=<(android_toolchain)/..',
+                    ],
+                  }],
+                  ['mips_dsp_rev==1', {
+                    'cflags': ['-mdsp'],
+                  }],
+                  ['mips_dsp_rev==2', {
+                    'cflags': ['-mdspr2'],
+                  }],
+                ],
+                'cflags': [
+                  '-m<(mips_float_abi)-float'
+                ],
+                'ldflags': [
+                  '-Wl,--no-keep-memory'
+                ],
+                'cflags_cc': [
+                  '-Wno-uninitialized',
+                ],
+              }],
+              ['_toolset=="target" and _type=="executable"', {
+                'conditions': [
+                  ['OS=="linux"', {
+                    'ldflags': ['-pie'],
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['target_arch=="mips64el"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  ['mips_arch_variant=="r6"', {
+                    'conditions': [
+                      ['clang==1', {
+                        'conditions': [
+                          ['OS=="android"', {
+                            'cflags': [ '-target mips64el-linux-android', '-march=mips64el', '-mcpu=mips64r6', ],
+                            'ldflags': [ '-target mips64el-linux-android', ],
+                          }],
+                        ],
+                      }, { # clang==0
+                        'cflags': ['-mips64r6', '-Wa,-mips64r6'],
+                        'ldflags': ['-mips64r6'],
+                      }],
+                      ['mips_msa==1', {
+                        'cflags': ['-mmsa', '-mfp64', '-msched-weight', '-mload-store-pairs'],
+                      }],
+                    ],
+                  }],
+                  ['mips_arch_variant=="r2"', {
+                    'cflags': ['-mips64r2', '-Wa,-mips64r2'],
+                    'ldflags': ['-mips64r2'],
+                  }],
+                  ['clang==1', {
+                    'cflags!': [
+                      # Clang does not support the following options.
+                      '-finline-limit=64',
+                    ],
+                    # TODO(gordanac) Enable integrated-as.
+                    'cflags': [ '-fno-integrated-as' ],
+                    'conditions': [
+                      ['OS=="android"', {
+                        'cflags': [
+                          # Else /usr/bin/as gets picked up.
+                          '-B<(android_toolchain)',
+                        ],
+                      }],
+                    ],
+                  }],
+                  ['clang==1 and OS=="android"', {
+                    'ldflags': [
+                      # Let clang find the ld in the NDK.
+                      '--gcc-toolchain=<(android_toolchain)/..',
+                    ],
+                  }],
+                ],
+
+                'cflags_cc': [
+                  '-Wno-uninitialized',
+                ],
+              }],
+            ],
+          }],
+          ['linux_fpic==1', {
+            'cflags': [
+              '-fPIC',
+            ],
+            'ldflags': [
+              '-fPIC',
+            ],
+          }],
+          ['sysroot!=""', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '--sysroot=<(sysroot)',
+                ],
+                'ldflags': [
+                  '--sysroot=<(sysroot)',
+                  '<!(<(DEPTH)/build/linux/sysroot_ld_path.sh <(sysroot))',
+                ],
+              }]]
+          }],
+          ['clang==1', {
+            'cflags': [
+              # See http://crbug.com/110262
+              '-fcolor-diagnostics',
+            ],
+            'cflags_cc': [
+              # gnu++11 instead of c++11 is needed because some code uses
+              # typeof() (a GNU extension).
+              # TODO(thakis): Eventually switch this to c++11 instead,
+              # http://crbug.com/427584
+              '-std=gnu++11',
+            ],
+          }],
+          ['clang==1 and chromeos==1', {
+            'cflags': [
+              # TODO(thakis): Remove, http://crbug.com/263960
+              '-Wno-reserved-user-defined-literal',
+            ],
+          }],
+          ['clang==0 and host_clang==1', {
+            'target_conditions': [
+              ['_toolset=="host"', {
+                'cflags_cc': [ '-std=gnu++11', ],
+              }],
+            ],
+          }],
+          ['clang==1 and clang_use_chrome_plugins==1', {
+            'cflags': [
+              '<@(clang_chrome_plugins_flags)',
+            ],
+          }],
+          ['clang==1 and clang_load!=""', {
+            'cflags': [
+              '-Xclang', '-load', '-Xclang', '<(clang_load)',
+            ],
+          }],
+          ['clang==1 and clang_add_plugin!=""', {
+            'cflags': [
+              '-Xclang', '-add-plugin', '-Xclang', '<(clang_add_plugin)',
+            ],
+          }],
+          ['clang==1 and target_arch=="ia32"', {
+            'cflags': [
+              # Else building libyuv gives clang's register allocator issues,
+              # see llvm.org/PR15798 / crbug.com/233709
+              '-momit-leaf-frame-pointer',
+              # Align the stack on 16-byte boundaries, http://crbug.com/418554.
+              '-mstack-alignment=16',
+              '-mstackrealign',
+            ],
+          }],
+          # Common options for AddressSanitizer, LeakSanitizer,
+          # ThreadSanitizer, MemorySanitizer and non-official CFI builds.
+          ['asan==1 or lsan==1 or tsan==1 or msan==1 or ubsan==1 or ubsan_security==1 or ubsan_vptr==1 or '
+           '(cfi_vptr==1 and buildtype!="Official")', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fno-omit-frame-pointer',
+                  '-gline-tables-only',
+                ],
+                'cflags!': [
+                  '-fomit-frame-pointer',
+                ],
+              }],
+            ],
+          }],
+          ['asan==1 or lsan==1 or tsan==1 or msan==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'ldflags!': [
+                  # Functions interposed by the sanitizers can make ld think
+                  # that some libraries aren't needed when they actually are,
+                  # http://crbug.com/234010. As workaround, disable --as-needed.
+                  '-Wl,--as-needed',
+                ],
+                'defines': [
+                  'MEMORY_TOOL_REPLACES_ALLOCATOR',
+                  'MEMORY_SANITIZER_INITIAL_SIZE',
+                ],
+              }],
+            ],
+          }],
+          ['asan==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize=address',
+                  # TODO(eugenis): Re-enable. http://crbug.com/427202
+                  #'-fsanitize-blacklist=<(asan_blacklist)',
+                ],
+                'ldflags': [
+                  '-fsanitize=address',
+                ],
+              }],
+            ],
+            'conditions': [
+              ['OS=="mac"', {
+                'cflags': [
+                  '-mllvm -asan-globals=0',  # http://crbug.com/352073
+                ],
+              }],
+            ],
+          }],
+          ['ubsan==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  ['chromecast==0', {
+                    'cflags': [
+                      # Employ the experimental PBQP register allocator to avoid
+                      # slow compilation on files with too many basic blocks.
+                      # See http://crbug.com/426271.
+                      '-mllvm -regalloc=pbqp',
+                      # Speculatively use coalescing to slightly improve the code
+                      # generated by PBQP regallocator. May increase compile time.
+                      '-mllvm -pbqp-coalescing',
+                    ],
+                  }],
+                ],
+                'cflags': [
+                  # FIXME: work on enabling more flags and getting rid of false
+                  # positives. http://crbug.com/174801.
+                  '-fsanitize=bounds',
+                  '-fsanitize=float-divide-by-zero',
+                  '-fsanitize=integer-divide-by-zero',
+                  '-fsanitize=null',
+                  '-fsanitize=object-size',
+                  '-fsanitize=return',
+                  '-fsanitize=returns-nonnull-attribute',
+                  '-fsanitize=shift-exponent',
+                  '-fsanitize=signed-integer-overflow',
+                  '-fsanitize=unreachable',
+                  '-fsanitize=vla-bound',
+                  '-fsanitize-blacklist=<(ubsan_blacklist)',
+                ],
+                'cflags_cc!': [
+                  '-fno-rtti',
+                ],
+                'cflags!': [
+                  '-fno-rtti',
+                ],
+                'ldflags': [
+                  '-fsanitize=undefined',
+                ],
+                'defines': [
+                  'UNDEFINED_SANITIZER',
+                ],
+              }],
+            ],
+          }],
+          ['ubsan_security==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize=signed-integer-overflow,shift,vptr',
+                  '-fsanitize-blacklist=<(ubsan_security_blacklist)',
+                ],
+                'cflags_cc!': [
+                  '-fno-rtti',
+                ],
+                'cflags!': [
+                  '-fno-rtti',
+                ],
+                'ldflags': [
+                  '-fsanitize=signed-integer-overflow,shift,vptr',
+                ],
+                'defines': [
+                  'UNDEFINED_SANITIZER',
+                ],
+              }],
+            ],
+          }],
+          ['ubsan_vptr==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize=vptr',
+                  '-fsanitize-blacklist=<(ubsan_vptr_blacklist)',
+                ],
+                'cflags_cc!': [
+                  '-fno-rtti',
+                ],
+                'cflags!': [
+                  '-fno-rtti',
+                ],
+                'ldflags': [
+                  '-fsanitize=vptr',
+                ],
+                'defines': [
+                  'UNDEFINED_SANITIZER',
+                ],
+              }],
+            ],
+          }],
+          ['sanitizer_coverage!=""', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize-coverage=<(sanitizer_coverage)',
+                ],
+                'defines': [
+                  'SANITIZER_COVERAGE',
+                ],
+              }],
+            ],
+          }],
+          ['sanitizer_coverage!="" and target_arch=="arm"', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-mllvm -sanitizer-coverage-block-threshold=0',  # http://crbug.com/517105
+                ],
+              }],
+            ],
+          }],
+          ['asan_field_padding!=0', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize-address-field-padding=<(asan_field_padding)',
+                ],
+              }],
+            ],
+          }],
+          ['lsan==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize=leak',
+                ],
+                'ldflags': [
+                  '-fsanitize=leak',
+                ],
+                'defines': [
+                  'LEAK_SANITIZER',
+                  'WTF_USE_LEAK_SANITIZER=1',
+                ],
+              }],
+            ],
+          }],
+          ['tsan==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize=thread',
+                  '-fsanitize-blacklist=<(tsan_blacklist)',
+                ],
+                'ldflags': [
+                  '-fsanitize=thread',
+                ],
+                'defines': [
+                  'THREAD_SANITIZER',
+                  'DYNAMIC_ANNOTATIONS_EXTERNAL_IMPL=1',
+                  'WTF_USE_DYNAMIC_ANNOTATIONS_NOIMPL=1',
+                ],
+              }],
+            ],
+          }],
+          ['msan==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize=memory',
+                  '-fsanitize-memory-track-origins=<(msan_track_origins)',
+                  '-fsanitize-blacklist=<(msan_blacklist)',
+                ],
+                'ldflags': [
+                  '-fsanitize=memory',
+                ],
+                'defines': [
+                  'MEMORY_SANITIZER',
+                ],
+              }],
+            ],
+          }],
+          ['use_instrumented_libraries==1', {
+            'dependencies': [
+              '<(DEPTH)/third_party/instrumented_libraries/instrumented_libraries.gyp:instrumented_libraries',
+            ],
+          }],
+          ['use_prebuilt_instrumented_libraries==1', {
+            'dependencies': [
+              '<(DEPTH)/third_party/instrumented_libraries/instrumented_libraries.gyp:prebuilt_instrumented_libraries',
+            ],
+          }],
+          ['use_custom_libcxx==1', {
+            'dependencies': [
+              '<(DEPTH)/buildtools/third_party/libc++/libc++.gyp:libcxx_proxy',
+            ],
+          }],
+          ['order_profiling!=0 and OS=="android"', {
+            'target_conditions' : [
+              ['_toolset=="target"', {
+                'cflags': ['-finstrument-functions'],
+                'defines': ['CYGPROFILE_INSTRUMENTATION'],
+              }],
+            ],
+          }],
+          # Clang doesn't understand -finstrument-functions-exclude-file-list=.
+          ['order_profiling!=0 and OS=="android" and clang==0', {
+            'target_conditions' : [
+              ['_toolset=="target"', {
+                'cflags': [
+                  # Allow mmx intrinsics to inline, so that the
+                  # compiler can expand the intrinsics.
+                  '-finstrument-functions-exclude-file-list=mmintrin.h',
+                  # Avoids errors with current NDK:
+                  # "third_party/android_tools/ndk/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/include/arm_neon.h:3426:3: error: argument must be a constant"
+                  '-finstrument-functions-exclude-file-list=arm_neon.h',
+                ],
+              }],
+            ],
+          }],
+          ['linux_dump_symbols==1', {
+            'cflags': [ '-g' ],
+            'conditions': [
+              ['OS=="linux" and host_arch=="ia32" and linux_use_bundled_gold==0', {
+                'target_conditions': [
+                  ['_toolset=="target"', {
+                    'ldflags': [
+                      # Attempt to use less memory to prevent the linker from
+                      # running out of address space. Considering installing a
+                      # 64-bit kernel and switching to a 64-bit linker.
+                      '-Wl,--no-keep-memory',
+                    ],
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['use_allocator!="tcmalloc"', {
+            'defines': ['NO_TCMALLOC'],
+          }],
+          ['linux_use_gold_flags==1', {
+            # Newer gccs and clangs support -fuse-ld, use the flag to force gold
+            # selection.
+            # gcc -- http://gcc.gnu.org/onlinedocs/gcc-4.8.0/gcc/Optimize-Options.html
+            'ldflags': [ '-fuse-ld=gold', ],
+
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'conditions': [
+                  # TODO(thestig): Enable this for disabled cases.
+                  [ 'linux_use_bundled_binutils==1', {
+                    'ldflags': [
+                      # Experimentation found that using four linking threads
+                      # saved ~20% of link time.
+                      # https://groups.google.com/a/chromium.org/group/chromium-dev/browse_thread/thread/281527606915bb36
+                      # Only apply this to the target linker, since the host
+                      # linker might not be gold, but isn't used much anyway.
+                      '-Wl,--threads',
+                      '-Wl,--thread-count=4',
+                    ],
+                  }],
+                  # TODO(thestig): Enable this for disabled cases.
+                  [ 'buildtype!="Official" and chromeos==0 and release_valgrind_build==0 and asan==0 and lsan==0 and tsan==0 and msan==0 and ubsan==0 and ubsan_security==0 and ubsan_vptr==0', {
+                    'ldflags': [
+                      '-Wl,--detect-odr-violations',
+                    ],
+                  }],
+                ],
+              }],
+            ],
+            'conditions': [
+              ['release_valgrind_build==0 and order_profiling==0 and asan==0 and msan==0 and lsan==0 and tsan==0', {
+                'target_conditions': [
+                  ['_toolset=="target"', {
+                    'ldflags': [
+                      '-Wl,--icf=<(gold_icf_level)',
+                    ],
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['linux_use_bundled_binutils==1', {
+            'cflags': [
+              '-B<!(cd <(DEPTH) && pwd -P)/<(binutils_dir)',
+            ],
+          }],
+          ['linux_use_bundled_gold==1 and '
+           'not (clang==0 and (use_lto==1 or use_lto_o2==1))', {
+            # Put our binutils, which contains gold in the search path. We pass
+            # the path to gold to the compiler. gyp leaves unspecified what the
+            # cwd is when running the compiler, so the normal gyp path-munging
+            # fails us. This hack gets the right path.
+            #
+            # Disabled when using GCC LTO because GCC also uses the -B search
+            # path at link time to find "as", and our bundled "as" can only
+            # target x86.
+            'ldflags': [
+              '-B<!(cd <(DEPTH) && pwd -P)/<(binutils_dir)',
+            ],
+          }],
+          # Some binutils 2.23 releases may or may not have new dtags enabled,
+          # but they are all compatible with --disable-new-dtags,
+          # because the new dynamic tags are not created by default.
+          ['binutils_version>=223', {
+            # Newer binutils don't set DT_RPATH unless you disable "new" dtags
+            # and the new DT_RUNPATH doesn't work without --no-as-needed flag.
+            # FIXME(mithro): Figure out the --as-needed/--no-as-needed flags
+            # inside this file to allow usage of --no-as-needed and removal of
+            # this flag.
+            'ldflags': [
+              '-Wl,--disable-new-dtags',
+            ],
+          }],
+          ['clang==0', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags_cc': [
+                  '-std=gnu++11',
+                  # See comment for -Wno-c++11-narrowing.
+                  '-Wno-narrowing',
+                ],
+              }],
+            ],
+          }],
+          ['clang==0 and host_clang==0', {
+            'target_conditions': [
+              ['_toolset=="host"', {
+                'cflags_cc': [
+                  '-std=gnu++11',
+                  # See comment for -Wno-c++11-narrowing.
+                  '-Wno-narrowing',
+                ],
+              }],
+            ],
+          }],
+          ['clang==0 and chromeos==1', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags_cc': [
+                  # TODO(thakis): Remove, http://crbug.com/263960
+                  '-Wno-literal-suffix',
+                ],
+              }],
+            ],
+          }],
+          ['clang==0 and host_clang==0 and chromeos==1', {
+            'target_conditions': [
+              ['_toolset=="host"', {
+                'cflags_cc': [
+                  # TODO(thakis): Remove, http://crbug.com/263960
+                  '-Wno-literal-suffix',
+                ],
+              }],
+            ],
+          }],
+        ],
+      },
+    }],
+    # *BSD-specific options; note that most *BSD options are set above,
+    # with Linux.
+    ['OS=="openbsd" or OS=="freebsd"', {
+      'target_defaults': {
+        'ldflags': [
+          '-Wl,--no-keep-memory',
+        ],
+      },
+    }],
+    # Android-specific options; note that most are set above with Linux.
+    ['OS=="android"', {
+      'variables': {
+        # Placing this variable here prevents from forking libvpx, used
+        # by remoting.  Remoting is off, so it needn't built,
+        # so forking it's deps seems like overkill.
+        # But this variable need defined to properly run gyp.
+        # A proper solution is to have an OS==android conditional
+        # in third_party/libvpx/libvpx.gyp to define it.
+        'libvpx_path': 'lib/linux/arm',
+      },
+      'target_defaults': {
+        'variables': {
+          'release_extra_cflags%': '',
+          'conditions': [
+            # If we're using the components build, append "cr" to all shared
+            # libraries to avoid naming collisions with android system library
+            # versions with the same name (e.g. skia, icu).
+            ['component=="shared_library"', {
+              'android_product_extension': 'cr.so',
+            }, {
+              'android_product_extension': 'so',
+            } ],
+          ],
+        },
+        'target_conditions': [
+          ['_type=="shared_library"', {
+            'product_extension': '<(android_product_extension)',
+          }],
+
+          # Settings for building device targets using Android's toolchain.
+          # These are based on the setup.mk file from the Android NDK.
+          #
+          # The NDK Android executable link step looks as follows:
+          #  $LDFLAGS
+          #  $(TARGET_CRTBEGIN_DYNAMIC_O)  <-- crtbegin.o
+          #  $(PRIVATE_OBJECTS)            <-- The .o that we built
+          #  $(PRIVATE_STATIC_LIBRARIES)   <-- The .a that we built
+          #  $(TARGET_LIBGCC)              <-- libgcc.a
+          #  $(PRIVATE_SHARED_LIBRARIES)   <-- The .so that we built
+          #  $(PRIVATE_LDLIBS)             <-- System .so
+          #  $(TARGET_CRTEND_O)            <-- crtend.o
+          #
+          # For now the above are approximated for executables by adding
+          # crtbegin.o to the end of the ldflags and 'crtend.o' to the end
+          # of 'libraries'.
+          #
+          # The NDK Android shared library link step looks as follows:
+          #  $LDFLAGS
+          #  $(PRIVATE_OBJECTS)            <-- The .o that we built
+          #  -l,--whole-archive
+          #  $(PRIVATE_WHOLE_STATIC_LIBRARIES)
+          #  -l,--no-whole-archive
+          #  $(PRIVATE_STATIC_LIBRARIES)   <-- The .a that we built
+          #  $(TARGET_LIBGCC)              <-- libgcc.a
+          #  $(PRIVATE_SHARED_LIBRARIES)   <-- The .so that we built
+          #  $(PRIVATE_LDLIBS)             <-- System .so
+          #
+          # For now, assume that whole static libraries are not needed.
+          #
+          # For both executables and shared libraries, add the proper
+          # libgcc.a to the start of libraries which puts it in the
+          # proper spot after .o and .a files get linked in.
+          #
+          # TODO: The proper thing to do longer-tem would be proper gyp
+          # support for a custom link command line.
+          ['_toolset=="target"', {
+            'cflags!': [
+              '-pthread',  # Not supported by Android toolchain.
+            ],
+            'cflags': [
+              '-ffunction-sections',
+              '-funwind-tables',
+              '-g',
+              '-fstack-protector',
+              '-fno-short-enums',
+              '-finline-limit=64',
+              '<@(release_extra_cflags)',
+              '--sysroot=<(android_ndk_sysroot)',
+            ],
+            'cflags_cc': [
+              # NOTE: The libc++ header include paths below are specified in
+              # cflags rather than include_dirs because they need to come
+              # after include_dirs.
+              # The include ordering here is important; change with caution.
+              '-isystem<(android_libcpp_include)',
+              '-isystem<(android_ndk_root)/sources/cxx-stl/llvm-libc++abi/libcxxabi/include',
+              '-isystem<(android_ndk_root)/sources/android/support/include',
+            ],
+            'defines': [
+              'ANDROID',
+              '__GNU_SOURCE=1',  # Necessary for clone()
+              # The NDK has these things, but doesn't define the constants
+              # to say that it does. Define them here instead.
+              'HAVE_SYS_UIO_H',
+              'ANDROID_NDK_VERSION=<(android_ndk_version)',
+            ],
+            'ldflags!': [
+              '-pthread',  # Not supported by Android toolchain.
+            ],
+            'ldflags': [
+              '-Wl,--build-id=sha1',
+              '-Wl,--no-undefined',
+              '--sysroot=<(android_ndk_sysroot)',
+              '-nostdlib',
+              '-L<(android_libcpp_libs_dir)',
+              # Don't allow visible symbols from libgcc or libc++ to be
+              # re-exported.
+              '-Wl,--exclude-libs=libgcc.a',
+              '-Wl,--exclude-libs=libc++_static.a',
+              # Don't allow visible symbols from libraries that contain
+              # assembly code with symbols that aren't hidden properly.
+              # http://crbug.com/448386
+              '-Wl,--exclude-libs=libcommon_audio.a',
+              '-Wl,--exclude-libs=libcommon_audio_neon.a',
+              '-Wl,--exclude-libs=libcommon_audio_sse2.a',
+              '-Wl,--exclude-libs=libiSACFix.a',
+              '-Wl,--exclude-libs=libisac_neon.a',
+              '-Wl,--exclude-libs=libopus.a',
+              '-Wl,--exclude-libs=libvpx.a',
+            ],
+            'libraries': [
+              '-l<(android_libcpp_library)',
+              '-latomic',
+              # Manually link the libgcc.a that the cross compiler uses.
+              '<!(<(android_toolchain)/*-gcc -print-libgcc-file-name)',
+              '-lc',
+              '-ldl',
+              '-lm',
+            ],
+            'conditions': [
+              ['component=="static_library"', {
+                'target_conditions': [
+                  ['use_native_jni_exports==0', {
+                    # Use a linker version script to strip JNI exports from
+                    # binaries which have not specifically asked to use them.
+                    'ldflags': [
+                      '-Wl,--version-script=<!(cd <(DEPTH) && pwd -P)/build/android/android_no_jni_exports.lst',
+                    ],
+                  }],
+                ],
+              }],
+              ['clang==1', {
+                'libraries!': [
+                  # Clang with libc++ does not require an explicit atomic
+                  # library reference.
+                  '-latomic',
+                ],
+                'cflags': [
+                  # Work around incompatibilities between bionic and clang
+                  # headers.
+                  '-D__compiler_offsetof=__builtin_offsetof',
+                  '-Dnan=__builtin_nan',
+                ],
+                'cflags!': [
+                  # Clang does not support the following options.
+                  '-finline-limit=64',
+                ],
+                'conditions': [
+                  ['target_arch=="arm"', {
+                    'cflags': [
+                      '-target arm-linux-androideabi',
+                    ],
+                    'ldflags': [
+                      '-target arm-linux-androideabi',
+                    ],
+                  }],
+                  ['target_arch=="ia32"', {
+                    'cflags': [
+                      '-target i686-linux-androideabi',
+                    ],
+                    'ldflags': [
+                      '-target i686-linux-androideabi',
+                    ],
+                  }],
+                  # Place holder for arm64 support, not tested.
+                  # TODO: Enable clang support for Android Arm64. http://crbug.com/539781
+                  ['target_arch=="arm64"', {
+                    'cflags': [
+                      '-target aarch64-linux-androideabi',
+                    ],
+                    'ldflags': [
+                      '-target aarch64-linux-androideabi',
+                    ],
+                  }],
+                  # Place holder for x64 support, not tested.
+                  # TODO: Enable clang support for Android x64. http://crbug.com/539781
+                  ['target_arch=="x64"', {
+                    'cflags': [
+                      '-target x86_64-linux-androideabi',
+                    ],
+                    'ldflags': [
+                      '-target x86_64-linux-androideabi',
+                    ],
+                  }],
+                ],
+              }],
+              ['asan==1', {
+                'cflags': [
+                  # Android build relies on -Wl,--gc-sections removing
+                  # unreachable code. ASan instrumentation for globals inhibits
+                  # this and results in a library with unresolvable relocations.
+                  # TODO(eugenis): find a way to reenable this.
+                  '-mllvm -asan-globals=0',
+                ],
+              }],
+              ['target_arch == "arm" and order_profiling==0', {
+                'ldflags': [
+                  # Enable identical code folding to reduce size.
+                  '-Wl,--icf=<(gold_icf_level)',
+                ],
+              }],
+              ['target_arch=="ia32"', {
+                # The x86 toolchain currently has problems with stack-protector.
+                'cflags!': [
+                  '-fstack-protector',
+                ],
+                'cflags': [
+                  '-fno-stack-protector',
+                ],
+              }],
+            ],
+            'target_conditions': [
+              ['_type=="executable"', {
+                'cflags': [
+                  '-fPIE',
+                ],
+                'ldflags': [
+                  '-Bdynamic',
+                  '-Wl,--gc-sections',
+                  '-Wl,-z,nocopyreloc',
+                  '-pie',
+                  # crtbegin_dynamic.o should be the last item in ldflags.
+                  '<(android_ndk_lib)/crtbegin_dynamic.o',
+                ],
+                'libraries': [
+                  # crtend_android.o needs to be the last item in libraries.
+                  # Do not add any libraries after this!
+                  '<(android_ndk_lib)/crtend_android.o',
+                ],
+              }],
+              ['_type=="shared_library" or _type=="loadable_module"', {
+                'ldflags': [
+                  '-Wl,-shared,-Bsymbolic',
+                  # crtbegin_so.o should be the last item in ldflags.
+                  '<(android_ndk_lib)/crtbegin_so.o',
+                ],
+                'libraries': [
+                  # crtend_so.o needs to be the last item in libraries.
+                  # Do not add any libraries after this!
+                  '<(android_ndk_lib)/crtend_so.o',
+                ],
+              }],
+            ],
+          }],
+          # Settings for building host targets using the system toolchain.
+          ['_toolset=="host"', {
+            'cflags!': [
+              # Due to issues in Clang build system, using ASan on 32-bit
+              # binaries on x86_64 host is problematic.
+              # TODO(eugenis): re-enable.
+              '-fsanitize=address',
+            ],
+            'ldflags!': [
+              '-fsanitize=address',
+              '-Wl,-z,noexecstack',
+              '-Wl,--gc-sections',
+              '-Wl,-O1',
+              '-Wl,--as-needed',
+              '-Wl,--warn-shared-textrel',
+              '-Wl,--fatal-warnings',
+            ],
+          }],
+          # Settings for building host targets on mac.
+          ['_toolset=="host" and host_os=="mac"', {
+            'ldflags!': [
+              '-Wl,-z,now',
+              '-Wl,-z,relro',
+            ],
+          }],
+        ],
+      },
+    }],
+    ['OS=="solaris"', {
+      'cflags!': ['-fvisibility=hidden'],
+      'cflags_cc!': ['-fvisibility-inlines-hidden'],
+    }],
+    ['OS=="mac" or OS=="ios"', {
+      'target_defaults': {
+        'mac_bundle': 0,
+        'xcode_settings': {
+          'ALWAYS_SEARCH_USER_PATHS': 'NO',
+          'CLANG_CXX_LANGUAGE_STANDARD': 'c++11',  # -std=c++11
+          # Don't link in libarclite_macosx.a, see http://crbug.com/156530.
+          'CLANG_LINK_OBJC_RUNTIME': 'NO',          # -fno-objc-link-runtime
+          # Warn if automatic synthesis is triggered with
+          # the -Wobjc-missing-property-synthesis flag.
+          'CLANG_WARN_OBJC_MISSING_PROPERTY_SYNTHESIS': 'YES',
+          'COPY_PHASE_STRIP': 'NO',
+          'GCC_C_LANGUAGE_STANDARD': 'c99',         # -std=c99
+          'GCC_CW_ASM_SYNTAX': 'NO',                # No -fasm-blocks
+          'GCC_ENABLE_CPP_EXCEPTIONS': 'NO',        # -fno-exceptions
+          'GCC_ENABLE_CPP_RTTI': 'NO',              # -fno-rtti
+          'GCC_ENABLE_PASCAL_STRINGS': 'NO',        # No -mpascal-strings
+          # GCC_INLINES_ARE_PRIVATE_EXTERN maps to -fvisibility-inlines-hidden
+          'GCC_INLINES_ARE_PRIVATE_EXTERN': 'YES',
+          'GCC_OBJC_CALL_CXX_CDTORS': 'YES',        # -fobjc-call-cxx-cdtors
+          'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',      # -fvisibility=hidden
+          'GCC_THREADSAFE_STATICS': 'NO',           # -fno-threadsafe-statics
+          'GCC_TREAT_WARNINGS_AS_ERRORS': 'YES',    # -Werror
+          'GCC_VERSION': 'com.apple.compilers.llvm.clang.1_0',
+          'USE_HEADERMAP': 'NO',
+          'WARNING_CFLAGS': [
+            '-Wall',
+            '-Wextra',
+            # Don't warn about unused function parameters.
+            '-Wno-unused-parameter',
+            # Don't warn about the "struct foo f = {0};" initialization
+            # pattern.
+            '-Wno-missing-field-initializers',
+            # This warns on selectors from Cocoa headers (-length, -set).
+            # cfe-dev is currently discussing the merits of this warning.
+            # TODO(thakis): Reevaluate what to do with this, based on the
+            # cfe-dev discussion.
+            '-Wno-selector-type-mismatch',
+          ],
+          'conditions': [
+            ['chromium_mac_pch', {'GCC_PRECOMPILE_PREFIX_HEADER': 'YES'},
+                                 {'GCC_PRECOMPILE_PREFIX_HEADER': 'NO'}
+            ],
+            ['clang==1', {
+              'OTHER_CFLAGS': [
+                # See http://crbug.com/110262
+                '-fcolor-diagnostics',
+              ],
+            }],
+            # Note that the prebuilt Clang binaries should not be used for iOS
+            # development except for ASan builds.
+            ['clang_xcode==0', {
+              'CC': '$(SOURCE_ROOT)/<(clang_dir)/clang',
+              'LDPLUSPLUS': '$(SOURCE_ROOT)/<(clang_dir)/clang++',
+            }],
+            ['clang==1 and clang_xcode==0 and clang_use_chrome_plugins==1', {
+              'OTHER_CFLAGS': [
+                '<@(clang_chrome_plugins_flags)',
+              ],
+            }],
+            ['clang==1 and clang_xcode==0 and clang_load!=""', {
+              'OTHER_CFLAGS': [
+                '-Xclang', '-load', '-Xclang', '<(clang_load)',
+              ],
+            }],
+            ['clang==1 and clang_xcode==0 and clang_add_plugin!=""', {
+              'OTHER_CFLAGS': [
+                '-Xclang', '-add-plugin', '-Xclang', '<(clang_add_plugin)',
+              ],
+            }],
+          ],
+        },
+        'conditions': [
+          ['clang==1', {
+            'variables': {
+              'clang_dir': '../third_party/llvm-build/Release+Asserts/bin',
+            },
+          }],
+          ['asan==1', {
+            'xcode_settings': {
+              'OTHER_CFLAGS': [
+                '-fsanitize=address',
+                '-mllvm -asan-globals=0',  # http://crbug.com/352073
+                '-gline-tables-only',
+              ],
+            },
+          }],
+          ['sanitizer_coverage!=""', {
+            'target_conditions': [
+              ['_toolset=="target"', {
+                'cflags': [
+                  '-fsanitize-coverage=<(sanitizer_coverage)',
+                ],
+                'defines': [
+                  'SANITIZER_COVERAGE',
+                ],
+              }],
+            ],
+          }],
+        ],
+        'target_conditions': [
+          ['_type!="static_library"', {
+            'xcode_settings': {'OTHER_LDFLAGS': ['-Wl,-search_paths_first']},
+            'conditions': [
+              ['asan==1', {
+                'xcode_settings': {
+                  'OTHER_LDFLAGS': [
+                    '-fsanitize=address',
+                  ],
+                },
+              }],
+              ['mac_write_linker_maps==1', {
+                'xcode_settings': {
+                  'OTHER_LDFLAGS': [
+                    '-Wl,-map,>(_target_name).map',
+                  ],
+                },
+              }],
+            ],
+          }],
+          ['_mac_bundle', {
+            'xcode_settings': {'OTHER_LDFLAGS': ['-Wl,-ObjC']},
+            'target_conditions': [
+              ['_type=="executable"', {
+                'conditions': [
+                  ['asan==1', {
+                    'postbuilds': [
+                      {
+                        'variables': {
+                          # Define copy_asan_dylib_path in a variable ending in
+                          # _path so that gyp understands it's a path and
+                          # performs proper relativization during dict merging.
+                          'copy_asan_dylib_path':
+                            'mac/copy_asan_runtime_dylib.sh',
+                        },
+                        'postbuild_name': 'Copy ASan runtime dylib',
+                        'action': [
+                          '<(copy_asan_dylib_path)',
+                        ],
+                      },
+                    ],
+                  }],
+                ],
+              }],
+            ],
+          }],
+        ],  # target_conditions
+      },  # target_defaults
+    }],  # OS=="mac" or OS=="ios"
+    ['OS=="mac"', {
+      'target_defaults': {
+        'defines': [
+          # Prevent Mac OS X AssertMacros.h from defining macros that collide
+          # with common names, like 'check', 'require', and 'verify'.
+          # (Included by system header. Also exists on iOS but not included.)
+          # http://opensource.apple.com/source/CarbonHeaders/CarbonHeaders-18.1/AssertMacros.h
+          '__ASSERT_MACROS_DEFINE_VERSIONS_WITHOUT_UNDERSCORE=0',
+        ],
+        'variables': {
+          # These should end with %, but there seems to be a bug with % in
+          # variables that are intended to be set to different values in
+          # different targets, like these.
+          # Strip debugging symbols from the target.
+          'mac_strip': '<(mac_strip_release)',
+          'conditions': [
+            ['asan==1', {
+              'conditions': [
+                ['mac_want_real_dsym=="default"', {
+                  'mac_real_dsym': 1,
+                }, {
+                  'mac_real_dsym': '<(mac_want_real_dsym)'
+                }],
+              ],
+            }, {
+              'conditions': [
+                ['mac_want_real_dsym=="default"', {
+                  'mac_real_dsym': 0, # Fake .dSYMs are fine in most cases.
+                }, {
+                  'mac_real_dsym': '<(mac_want_real_dsym)'
+                }],
+              ],
+            }],
+          ],
+        },
+        'configurations': {
+          'Release_Base': {
+            'conditions': [
+              ['branding=="Chrome" and buildtype=="Official"', {
+                'xcode_settings': {
+                  'OTHER_CFLAGS': [
+                    # The Google Chrome Framework dSYM generated by dsymutil has
+                    # grown larger than 4GB, which dsymutil can't handle. Reduce
+                    # the amount of debug symbols.
+                    '-fno-standalone-debug',  # See http://crbug.com/479841
+                  ]
+                },
+              }],
+            ],
+          },  # configuration "Release"
+        },  # configurations
+        'xcode_settings': {
+          # Tell the compiler to use libc++'s headers and the linker to link
+          # against libc++.  The latter part normally requires OS X 10.7,
+          # but we still support running on 10.6.  How does this work?  Two
+          # parts:
+          # 1. Chromium's clang doesn't error on -mmacosx-version-min=10.6
+          #    combined with -stdlib=libc++ (it normally silently produced a
+          #    binary that doesn't run on 10.6)
+          # 2. Further down, library_dirs is set to
+          #    third_party/libc++-static, which contains a static
+          #    libc++.a library.  The linker then links against that instead
+          #    of against /usr/lib/libc++.dylib when it sees the -lc++ flag
+          #    added by the driver.
+          #
+          # In component builds, just link to the system libc++.  This has
+          # the effect of making everything depend on libc++, which means
+          # component-build binaries won't run on 10.6 (no libc++ there),
+          # but for a developer-only configuration that's ok.  (We don't
+          # want to raise the deployment target yet so that official and
+          # dev builds have the same deployment target.  This affects
+          # things like which functions are considered deprecated.)
+          'CLANG_CXX_LIBRARY': 'libc++',  # -stdlib=libc++
+
+          'GCC_DYNAMIC_NO_PIC': 'NO',               # No -mdynamic-no-pic
+                                                    # (Equivalent to -fPIC)
+          # MACOSX_DEPLOYMENT_TARGET maps to -mmacosx-version-min
+          'MACOSX_DEPLOYMENT_TARGET': '<(mac_deployment_target)',
+          # Keep pch files below xcodebuild/.
+          'SHARED_PRECOMPS_DIR': '$(CONFIGURATION_BUILD_DIR)/SharedPrecompiledHeaders',
+          'OTHER_CFLAGS': [
+            # Someday this can be replaced by an 'GCC_STRICT_ALIASING': 'NO'
+            # xcode_setting, but not until all downstream projects' mac bots are
+            # using xcode >= 4.6, because that's when the default value of the
+            # flag in the compiler switched.  Pre-4.6, the value 'NO' for that
+            # setting is a no-op as far as xcode is concerned, but the compiler
+            # behaves differently based on whether -fno-strict-aliasing is
+            # specified or not.
+            '-fno-strict-aliasing',  # See http://crbug.com/32204.
+          ],
+        },
+        'target_conditions': [
+          ['>(nacl_untrusted_build)==0 and component=="static_library"', {
+            # See the comment for CLANG_CXX_LIBRARY above for what this does.
+            # The NaCl toolchains have their own toolchain and don't need this.
+            # ASan requires 10.7+ and clang implicitly adds -lc++abi in ASan
+            # mode.  Our libc++.a contains both libc++ and libc++abi in one
+            # library, so it doesn't work in that mode.
+            'conditions': [
+              ['asan==0', {
+                'library_dirs': [ '<(DEPTH)/third_party/libc++-static' ],
+              }],
+            ],
+          }],
+          ['_type=="executable"', {
+            # Turn on position-independence (ASLR) for executables. When
+            # PIE is on for the Chrome executables, the framework will
+            # also be subject to ASLR.
+            'xcode_settings': {
+              'OTHER_LDFLAGS': [
+                '-Wl,-pie',  # Position-independent executable (MH_PIE)
+              ],
+            },
+          }],
+          ['(_type=="executable" or _type=="shared_library" or \
+             _type=="loadable_module") and mac_strip!=0', {
+            'target_conditions': [
+              ['mac_real_dsym == 1', {
+                # To get a real .dSYM bundle produced by dsymutil, set the
+                # debug information format to dwarf-with-dsym.  Since
+                # strip_from_xcode will not be used, set Xcode to do the
+                # stripping as well.
+                'configurations': {
+                  'Release_Base': {
+                    'xcode_settings': {
+                      'DEBUG_INFORMATION_FORMAT': 'dwarf-with-dsym',
+                      'DEPLOYMENT_POSTPROCESSING': 'YES',
+                      'STRIP_INSTALLED_PRODUCT': 'YES',
+                      'conditions': [
+                        # Only strip non-ASan builds.
+                        ['asan==0', {
+                          'target_conditions': [
+                            ['_type=="shared_library" or _type=="loadable_module"', {
+                              # The Xcode default is to strip debugging symbols
+                              # only (-S).  Local symbols should be stripped as
+                              # well, which will be handled by -x.  Xcode will
+                              # continue to insert -S when stripping even when
+                              # additional flags are added with STRIPFLAGS.
+                              'STRIPFLAGS': '-x',
+                            }],  # _type=="shared_library" or _type=="loadable_module"
+                          ],  # target_conditions
+                        }, {  # asan != 0
+                          'STRIPFLAGS': '-S',
+                        }],
+                      ],
+                    },  # xcode_settings
+                  },  # configuration "Release"
+                },  # configurations
+              }, {  # mac_real_dsym != 1
+                # To get a fast fake .dSYM bundle, use a post-build step to
+                # produce the .dSYM and strip the executable.  strip_from_xcode
+                # only operates in the Release configuration.
+                'postbuilds': [
+                  {
+                    'variables': {
+                      # Define strip_from_xcode in a variable ending in _path
+                      # so that gyp understands it's a path and performs proper
+                      # relativization during dict merging.
+                      'strip_from_xcode_path': 'mac/strip_from_xcode',
+                    },
+                    'postbuild_name': 'Strip If Needed',
+                    'action': ['<(strip_from_xcode_path)'],
+                  },
+                ],  # postbuilds
+              }],  # mac_real_dsym
+            ],  # target_conditions
+          }],  # (_type=="executable" or _type=="shared_library" or
+               #  _type=="loadable_module") and mac_strip!=0
+        ],  # target_conditions
+      },  # target_defaults
+    }],  # OS=="mac"
+    ['OS=="ios"', {
+      'includes': [
+        'ios/coverage.gypi',
+      ],
+      'target_defaults': {
+        'xcode_settings' : {
+          'ENABLE_BITCODE': 'NO',
+          'CLANG_CXX_LIBRARY': 'libc++',  # -stdlib=libc++
+
+          'conditions': [
+            # Older Xcodes do not support -Wno-deprecated-register, so pass an
+            # additional flag to suppress the "unknown compiler option" error.
+            # Restrict this flag to builds that are either compiling with Xcode
+            # or compiling with Xcode's Clang.  This will allow Ninja builds to
+            # continue failing on unknown compiler options.
+            # TODO(rohitrao): This flag is temporary and should be removed as
+            # soon as the iOS bots are updated to use Xcode 5.1.
+            ['clang_xcode==1', {
+              'WARNING_CFLAGS': [
+                '-Wno-unknown-warning-option',
+                # It's not possible to achieve nullability completeness before
+                # all builders are running Xcode 7. crbug.com/499809
+                '-Wno-nullability-completeness',
+              ],
+              'OTHER_CPLUSPLUSFLAGS': [
+                '$(inherited)',
+                # TODO(ios): Remove once Xcode's libc++ has LLVM r256325
+                '-isystem <!(cd <(DEPTH) && pwd -P)/third_party/llvm-build/Release+Asserts/include/c++/v1',
+              ],
+            }],
+
+            # Limit the valid architectures depending on "target_subarch".
+            # This need to include the "arm" architectures but also the "x86"
+            # ones (they are used when building for the simulator).
+            ['target_subarch=="arm32"', {
+              'VALID_ARCHS': ['armv7', 'i386'],
+            }],
+            ['target_subarch=="arm64"', {
+              'VALID_ARCHS': ['arm64', 'x86_64'],
+            }],
+            ['target_subarch=="both"', {
+              'VALID_ARCHS': ['arm64', 'armv7', 'x86_64', 'i386'],
+            }],
+          ],
+        },
+        'target_conditions': [
+          ['_toolset=="host"', {
+            'xcode_settings': {
+              'SDKROOT': 'macosx<(mac_sdk)',  # -isysroot
+              'MACOSX_DEPLOYMENT_TARGET': '<(mac_deployment_target)',
+              'VALID_ARCHS': [
+                'x86_64',
+              ],
+              'ARCHS': [
+                'x86_64',
+              ],
+            },
+          }],
+          ['_toolset=="target"', {
+            'xcode_settings': {
+              # This section should be for overriding host settings. But,
+              # since we can't negate the iphone deployment target above, we
+              # instead set it here for target only.
+              'IPHONEOS_DEPLOYMENT_TARGET': '<(ios_deployment_target)',
+              'ARCHS': ['$(ARCHS_STANDARD_INCLUDING_64_BIT)'],
+            },
+          }],
+          ['_type=="executable"', {
+            'configurations': {
+              'Release_Base': {
+                'xcode_settings': {
+                  'DEPLOYMENT_POSTPROCESSING': 'YES',
+                  'STRIP_INSTALLED_PRODUCT': 'YES',
+                  'conditions': [
+                    ['buildtype=="Official"', {
+                      'DEBUG_INFORMATION_FORMAT': 'dwarf-with-dsym',
+                    }, {
+                      # Remove dSYM to reduce build time.
+                      'DEBUG_INFORMATION_FORMAT': 'dwarf',
+                    }],
+                  ],
+                },
+              },
+              'Debug_Base': {
+                'xcode_settings': {
+                  # Remove dSYM to reduce build time.
+                  'DEBUG_INFORMATION_FORMAT': 'dwarf',
+                },
+              },
+            },
+            'xcode_settings': {
+              'conditions': [
+                ['chromium_ios_signing', {
+                  # iOS SDK wants everything for device signed.
+                  'CODE_SIGN_IDENTITY[sdk=iphoneos*]': '<(chromium_ios_signing_identity)',
+                }, {
+                  'CODE_SIGNING_REQUIRED': 'NO',
+                  'CODE_SIGN_IDENTITY[sdk=iphoneos*]': '',
+                }],
+              ],
+            },
+          }],
+        ],  # target_conditions
+      },  # target_defaults
+    }],  # OS=="ios"
+    ['OS=="win"', {
+      'target_defaults': {
+        'defines': [
+          '_WIN32_WINNT=0x0A00',
+          'WINVER=0x0A00',
+          'WIN32',
+          '_WINDOWS',
+          'NOMINMAX',
+          'PSAPI_VERSION=1',
+          '_CRT_RAND_S',
+          'CERT_CHAIN_PARA_HAS_EXTRA_FIELDS',
+          'WIN32_LEAN_AND_MEAN',
+          '_ATL_NO_OPENGL',
+          '_SECURE_ATL',
+          # _HAS_EXCEPTIONS must match ExceptionHandling in msvs_settings.
+          '_HAS_EXCEPTIONS=0',
+          # Silence some warnings; we can't switch the the 'recommended'
+          # versions as they're not available on old OSs.
+          '_WINSOCK_DEPRECATED_NO_WARNINGS',
+        ],
+        'conditions': [
+          ['buildtype=="Official"', {
+            # In official builds, targets can self-select an optimization
+            # level by defining a variable named 'optimize', and setting it
+            # to one of
+            # - "size", optimizes for minimal code size - the default.
+            # - "speed", optimizes for speed over code size.
+            # - "max", whole program optimization and link-time code
+            #   generation. This is very expensive and should be used
+            #   sparingly.
+            'variables': {
+              'optimize%': 'size',
+            },
+            'msvs_settings': {
+              'VCLinkerTool': {
+                # Set /LTCG for the official builds.
+                'LinkTimeCodeGeneration': '1',
+                'AdditionalOptions': [
+                  # Set the number of LTCG code-gen threads to eight.
+                  # The default is four. This gives a 5-10% link speedup.
+                  '/cgthreads:8',
+                ],
+              },
+            },
+            'target_conditions': [
+              ['optimize=="size"', {
+                'msvs_settings': {
+                  'VCCLCompilerTool': {
+                    # 1, optimizeMinSpace, Minimize Size (/O1)
+                    'Optimization': '1',
+                    # 2, favorSize - Favor small code (/Os)
+                    'FavorSizeOrSpeed': '2',
+                    'conditions': [
+                      # TODO(thakis): Remove clang==0 here, crbug.com/598772
+                      ['full_wpo_on_official==1 and clang==0', {
+                        # This implies link time code generation.
+                        'WholeProgramOptimization': 'true',
+                      }],
+                    ],
+                  },
+                },
+              }],
+              # This config is used to avoid a problem in ffmpeg, see
+              # http://crbug.com/264459.
+              ['optimize=="size_no_ltcg"', {
+                'msvs_settings': {
+                  'VCCLCompilerTool': {
+                    # 1, optimizeMinSpace, Minimize Size (/O1)
+                    'Optimization': '1',
+                    # 2, favorSize - Favor small code (/Os)
+                    'FavorSizeOrSpeed': '2',
+                  },
+                },
+              }],
+              ['optimize=="speed"', {
+                'msvs_settings': {
+                  'VCCLCompilerTool': {
+                    # 2, optimizeMaxSpeed, Maximize Speed (/O2)
+                    'Optimization': '2',
+                    # 1, favorSpeed - Favor fast code (/Ot)
+                    'FavorSizeOrSpeed': '1',
+                    'conditions': [
+                      # TODO(thakis): Remove clang==0 here, crbug.com/598772
+                      ['full_wpo_on_official==1 and clang==0', {
+                        # This implies link time code generation.
+                        'WholeProgramOptimization': 'true',
+                      }],
+                    ],
+                  },
+                },
+              }],
+              ['optimize=="max"', {
+                # Disable Warning 4702 ("Unreachable code") for the WPO/PGO
+                # builds. Probably anything that this would catch that
+                # wouldn't be caught in a normal build isn't going to
+                # actually be a bug, so the incremental value of C4702 for
+                # PGO builds is likely very small.
+                'msvs_disabled_warnings': [
+                  4702
+                ],
+                'msvs_settings': {
+                  'VCCLCompilerTool': {
+                    # 2, optimizeMaxSpeed, Maximize Speed (/O2)
+                    'Optimization': '2',
+                    # 1, favorSpeed - Favor fast code (/Ot)
+                    'FavorSizeOrSpeed': '1',
+                  },
+                },
+                # TODO(thakis): Remove clang==0 here, https://crbug.com/598772
+                'conditions': [
+                  ['clang==0', {
+                    'msvs_settings': {
+                      'VCCLCompilerTool': {
+                        # This implies link time code generation.
+                        'WholeProgramOptimization': 'true',
+                      },
+                    },
+                  }],
+                ],
+              }],
+            ],
+          }],
+          ['msvs_xtree_patched!=1', {
+            # If xtree hasn't been patched, then we disable C4702. Otherwise,
+            # it's enabled. This will generally only be true for system-level
+            # installed Express users.
+            'msvs_disabled_warnings': [
+              4702, # unreachable code
+            ],
+          }],
+          ['full_wpo_on_official==1', {
+            # Disable Warning 4702 ("Unreachable code") for the WPO/PGO
+            # builds. Probably anything that this would catch that
+            # wouldn't be caught in a normal build isn't going to
+            # actually be a bug, so the incremental value of C4702 for
+            # PGO builds is likely very small.
+            'msvs_disabled_warnings': [
+              4702
+            ],
+          }],
+        ],
+        # Add extra include directories here that need to be in front of the
+        # installed and packaged include directories. This may be needed in
+        # order to force a particular SDK version, such as to get VS 2013 to use
+        # the Windows 10 SDK. Beware of making the INCLUDE variable excessively
+        # long, and be sure to make corresponding changes to
+        # build\toolchain\win\setup_toolchain.py
+        'msvs_system_include_dirs': [
+        ],
+        'msvs_cygwin_shell': 0,
+        'msvs_disabled_warnings': [
+          # C4091: 'typedef ': ignored on left of 'X' when no variable is
+          #                    declared.
+          # This happens in a number of Windows headers. Dumb.
+          4091,
+
+          # C4127: conditional expression is constant
+          # This warning can in theory catch dead code and other problems, but
+          # triggers in far too many desirable cases where the conditional
+          # expression is either set by macros or corresponds some legitimate
+          # compile-time constant expression (due to constant template args,
+          # conditionals comparing the sizes of different types, etc.).  Some of
+          # these can be worked around, but it's not worth it.
+          4127,
+
+          # C4351: new behavior: elements of array 'array' will be default
+          #        initialized
+          # This is a silly "warning" that basically just alerts you that the
+          # compiler is going to actually follow the language spec like it's
+          # supposed to, instead of not following it like old buggy versions
+          # did.  There's absolutely no reason to turn this on.
+          4351,
+
+          # C4355: 'this': used in base member initializer list
+          # It's commonly useful to pass |this| to objects in a class'
+          # initializer list.  While this warning can catch real bugs, most of
+          # the time the constructors in question don't attempt to call methods
+          # on the passed-in pointer (until later), and annotating every legit
+          # usage of this is simply more hassle than the warning is worth.
+          4355,
+
+          # C4503: 'identifier': decorated name length exceeded, name was
+          #        truncated
+          # This only means that some long error messages might have truncated
+          # identifiers in the presence of lots of templates.  It has no effect
+          # on program correctness and there's no real reason to waste time
+          # trying to prevent it.
+          4503,
+
+          # Warning C4589 says: "Constructor of abstract class ignores
+          # initializer for virtual base class." Disable this warning because it
+          # is flaky in VS 2015 RTM. It triggers on compiler generated
+          # copy-constructors in some cases.
+          4589,
+
+          # C4611: interaction between 'function' and C++ object destruction is
+          #        non-portable
+          # This warning is unavoidable when using e.g. setjmp/longjmp.  MSDN
+          # suggests using exceptions instead of setjmp/longjmp for C++, but
+          # Chromium code compiles without exception support.  We therefore have
+          # to use setjmp/longjmp for e.g. JPEG decode error handling, which
+          # means we have to turn off this warning (and be careful about how
+          # object destruction happens in such cases).
+          4611,
+
+          # TODO(maruel): These warnings are level 4. They will be slowly
+          # removed as code is fixed.
+          4100, # Unreferenced formal parameter
+          4121, # Alignment of a member was sensitive to packing
+          4244, # Conversion from 'type1' to 'type2', possible loss of data
+          4505, # Unreferenced local function has been removed
+          4510, # Default constructor could not be generated
+          4512, # Assignment operator could not be generated
+          4610, # Object can never be instantiated
+          4838, # Narrowing conversion. Doesn't seem to be very useful.
+          4995, # 'X': name was marked as #pragma deprecated
+          4996, # 'X': was declared deprecated (for GetVersionEx).
+
+          # These are variable shadowing warnings that are new in VS2015. We
+          # should work through these at some point -- they may be removed from
+          # the RTM release in the /W4 set.
+          4456, 4457, 4458, 4459,
+
+          # TODO(brucedawson): http://crbug.com/554200 4312 is a VS
+          # 2015 64-bit warning for integer to larger pointer
+          4312,
+
+          # TODO(brucedawson): http://crbug.com/593448 - C4595 is an 'illegal
+          # inline operator new' warning that is new in VS 2015 Update 2.
+          # This is equivalent to clang's no-inline-new-delete warning.
+          # See http://bugs.icu-project.org/trac/ticket/11122
+          4595,
+        ],
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'AdditionalOptions': ['/MP'],
+            'MinimalRebuild': 'false',
+            'BufferSecurityCheck': 'true',
+            'EnableFunctionLevelLinking': 'true',
+            'RuntimeTypeInfo': 'false',
+            'WarningLevel': '4',
+            'WarnAsError': 'true',
+            'DebugInformationFormat': '3',
+            # ExceptionHandling must match _HAS_EXCEPTIONS above.
+            'ExceptionHandling': '0',
+          },
+          'VCLibrarianTool': {
+            'AdditionalOptions': ['/ignore:4221'],
+            'AdditionalLibraryDirectories': [
+              '<(windows_sdk_path)/Lib/win8/um/x86',
+            ],
+          },
+          'VCLinkerTool': {
+            'AdditionalDependencies': [
+              'wininet.lib',
+              'dnsapi.lib',
+              'version.lib',
+              'msimg32.lib',
+              'ws2_32.lib',
+              'usp10.lib',
+              'psapi.lib',
+              'dbghelp.lib',
+              'winmm.lib',
+              'shlwapi.lib',
+            ],
+            'AdditionalLibraryDirectories': [
+              '<(windows_sdk_path)/Lib/win8/um/x86',
+            ],
+            'GenerateDebugInformation': 'true',
+            'MapFileName': '$(OutDir)\\$(TargetName).map',
+            'FixedBaseAddress': '1',
+            # SubSystem values:
+            #   0 == not set
+            #   1 == /SUBSYSTEM:CONSOLE
+            #   2 == /SUBSYSTEM:WINDOWS
+            # Most of the executables we'll ever create are tests
+            # and utilities with console output.
+            'SubSystem': '1',
+          },
+          'VCMIDLTool': {
+            'GenerateStublessProxies': 'true',
+            'TypeLibraryName': '$(InputName).tlb',
+            'OutputDirectory': '$(IntDir)',
+            'HeaderFileName': '$(InputName).h',
+            'DLLDataFileName': '$(InputName).dlldata.c',
+            'InterfaceIdentifierFileName': '$(InputName)_i.c',
+            'ProxyFileName': '$(InputName)_p.c',
+          },
+          'VCResourceCompilerTool': {
+            'Culture' : '1033',
+            'AdditionalIncludeDirectories': [
+              '<(DEPTH)',
+              '<(SHARED_INTERMEDIATE_DIR)',
+            ],
+          },
+          'target_conditions': [
+            ['_type=="executable"', {
+              'VCManifestTool': {
+                'EmbedManifest': 'true',
+              },
+            }],
+            ['_type=="executable" and ">(win_exe_compatibility_manifest)"!=""', {
+              'VCManifestTool': {
+                'AdditionalManifestFiles': [
+                  '>(win_exe_compatibility_manifest)',
+                ],
+              },
+            }],
+          ],
+          'conditions': [
+            # Building with Clang on Windows is a work in progress and very
+            # experimental. See crbug.com/82385.
+            # Keep this in sync with the similar blocks in build/config/compiler/BUILD.gn
+            ['clang==1', {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  # Don't warn about unused function parameters.
+                  # (This is also used on other platforms.)
+                  '-Wno-unused-parameter',
+                  # Don't warn about the "struct foo f = {0};" initialization
+                  # pattern.
+                  '-Wno-missing-field-initializers',
+
+                  # TODO(hans): Make this list shorter eventually, http://crbug.com/504657
+                  '-Wno-microsoft-enum-value',  # http://crbug.com/505296
+                  '-Wno-unknown-pragmas',  # http://crbug.com/505314
+                  '-Wno-microsoft-cast',  # http://crbug.com/550065
+                ],
+              },
+            }],
+            ['clang==1 and clang_use_chrome_plugins==1', {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  '<@(clang_chrome_plugins_flags)',
+                ],
+              },
+            }],
+            ['clang==1 and MSVS_VERSION == "2013"', {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  '-fmsc-version=1800',
+                ],
+              },
+            }],
+            ['clang==1 and MSVS_VERSION == "2015"', {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  '-fmsc-version=1900',
+                ],
+              },
+            }],
+            ['clang==1 and "<!(python <(DEPTH)/build/win/use_ansi_codes.py)"=="True"', {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  # cmd.exe doesn't understand ANSI escape codes by default,
+                  # so only enable them if something emulating them is around.
+                  '-fansi-escape-codes',
+                  # Also see http://crbug.com/110262
+                  '-fcolor-diagnostics',
+                ],
+              },
+            }],
+          ],
+        },
+      },
+    }],
+    ['disable_nacl==1', {
+      'target_defaults': {
+        'defines': [
+          'DISABLE_NACL',
+        ],
+      },
+    }],
+    ['OS=="win" and msvs_use_common_linker_extras', {
+      'target_defaults': {
+        'msvs_settings': {
+          'VCLinkerTool': {
+            'DelayLoadDLLs': [
+              'dbghelp.dll',
+              'dwmapi.dll',
+              'shell32.dll',
+              'uxtheme.dll',
+            ],
+          },
+        },
+        'configurations': {
+          'x86_Base': {
+            'msvs_settings': {
+              'VCLinkerTool': {
+                'AdditionalOptions': [
+                  '/safeseh',
+                  '/dynamicbase',
+                  '/ignore:4199',
+                  '/ignore:4221',
+                  '/nxcompat',
+                  '/largeaddressaware',
+                ],
+              },
+              'conditions': [
+                ['asan==1', {
+                  # TODO(asan/win): Move this down into the general
+                  # win-target_defaults section once the 64-bit asan runtime
+                  # exists.  See crbug.com/345874.
+                  'VCCLCompilerTool': {
+                    'AdditionalOptions': [
+                      '-fsanitize=address',
+                      '-fsanitize-blacklist=<(PRODUCT_DIR)/../../tools/memory/asan/blacklist_win.txt',
+                      # Omit variable info to speed up /Z7 links.
+                      '-gline-tables-only',
+                    ],
+                    'AdditionalIncludeDirectories': [
+                      # MSVC needs to be able to find the sanitizer headers when
+                      # invoked via /fallback. This is critical for using macros
+                      # like ASAN_UNPOISON_MEMORY_REGION in files where we fall
+                      # back.
+                      '<(DEPTH)/<(make_clang_dir)/lib/clang/<!(python <(DEPTH)/tools/clang/scripts/update.py --print-clang-version)/include_sanitizer',
+                    ],
+                  },
+                  'VCLinkerTool': {
+                    'AdditionalLibraryDirectories': [
+                      # TODO(hans): If make_clang_dir is absolute, this breaks.
+                      '<(DEPTH)/<(make_clang_dir)/lib/clang/<!(python <(DEPTH)/tools/clang/scripts/update.py --print-clang-version)/lib/windows',
+                    ],
+                  },
+                  'target_conditions': [
+                    ['component=="shared_library"', {
+                      'VCLinkerTool': {
+                        'AdditionalDependencies': [
+                           'clang_rt.asan_dynamic-i386.lib',
+                           'clang_rt.asan_dynamic_runtime_thunk-i386.lib',
+                        ],
+                      },
+                    }],
+                    ['_type=="executable" and component=="static_library"', {
+                      'VCLinkerTool': {
+                        'AdditionalDependencies': [
+                           'clang_rt.asan-i386.lib',
+                        ],
+                      },
+                    }],
+                    ['(_type=="shared_library" or _type=="loadable_module") and component=="static_library"', {
+                      'VCLinkerTool': {
+                        'AdditionalDependencies': [
+                           'clang_rt.asan_dll_thunk-i386.lib',
+                        ],
+                      },
+                    }],
+                  ],
+                }],
+                ['sanitizer_coverage!=""', {
+                  # TODO(asan/win): Move this down into the general
+                  # win-target_defaults section once the 64-bit asan runtime
+                  # exists.  See crbug.com/345874.
+                  'VCCLCompilerTool': {
+                    'AdditionalOptions': [
+                      '-fsanitize-coverage=<(sanitizer_coverage)',
+                    ],
+                  },
+                }],
+              ],
+            },
+            'conditions': [
+              ['sanitizer_coverage!=""', {
+                # TODO(asan/win): Move this down into the general
+                # win-target_defaults section once the 64-bit asan runtime
+                # exists.  See crbug.com/345874.
+                'defines': [
+                  'SANITIZER_COVERAGE',
+                ],
+              }],
+            ],
+          },
+          'x64_Base': {
+            'msvs_settings': {
+              'VCLinkerTool': {
+                'AdditionalOptions': [
+                  # safeseh is not compatible with x64
+                  '/dynamicbase',
+                  '/ignore:4199',
+                  '/ignore:4221',
+                  '/nxcompat',
+                ],
+              },
+            },
+          },
+        },
+      },
+    }],
+    ['enable_new_npdevice_api==1', {
+      'target_defaults': {
+        'defines': [
+          'ENABLE_NEW_NPDEVICE_API',
+        ],
+      },
+    }],
+    # Don't warn about the "typedef 'foo' locally defined but not used"
+    # for gcc 4.8 and higher.
+    # TODO: remove this flag once all builds work. See crbug.com/227506
+    ['clang==0', {
+      'target_defaults': {
+        'cflags': [ '-Wno-unused-local-typedefs' ],
+      },
+    }],
+    ['clang==0 and host_clang==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="host"', { 'cflags!': [ '-Wno-unused-local-typedefs' ]}],
+        ],
+      },
+    }],
+    ['clang==1 and ((OS!="mac" and OS!="ios") or clang_xcode==0) '
+        'and OS!="win"', {
+      'make_global_settings': [
+        ['CC', '<(make_clang_dir)/bin/clang'],
+        ['CXX', '<(make_clang_dir)/bin/clang++'],
+        ['CC.host', '$(CC)'],
+        ['CXX.host', '$(CXX)'],
+      ],
+    }],
+    ['clang==1 and OS=="win"', {
+      'make_global_settings': [
+        # On Windows, gyp's ninja generator only looks at CC.
+        ['CC', '<(make_clang_dir)/bin/clang-cl'],
+      ],
+    }],
+    ['use_lld==1 and OS=="win"', {
+      'make_global_settings': [
+        # Limited to Windows because lld-link is the driver that is
+        # compatible with link.exe.
+        ['LD', '<(make_clang_dir)/bin/lld-link'],
+        # lld-link includes a replacement for lib.exe that can produce thin
+        # archives and understands bitcode (for use_lto==1).
+        ['AR', '<(make_clang_dir)/bin/lld-link /lib /llvmlibthin'],
+      ],
+    }],
+    ['OS=="android" and clang==0', {
+      # Hardcode the compiler names in the Makefile so that
+      # it won't depend on the environment at make time.
+      'make_global_settings': [
+        ['CC', '<!(/bin/echo -n <(android_toolchain)/*-gcc)'],
+        ['CXX', '<!(/bin/echo -n <(android_toolchain)/*-g++)'],
+        ['CC.host', '<(host_cc)'],
+        ['CXX.host', '<(host_cxx)'],
+      ],
+    }],
+    ['OS=="linux" and target_arch=="mipsel" and host_arch!="mipsel" and chromeos==0 and clang==0', {
+      # Set default mips cross tools on linux.  These can be overridden
+      # using CC,CXX,CC.host and CXX.host environment variables.
+      'make_global_settings': [
+        ['CC', '<!(which mipsel-linux-gnu-gcc)'],
+        ['CXX', '<!(which mipsel-linux-gnu-g++)'],
+        ['CC.host', '<(host_cc)'],
+        ['CXX.host', '<(host_cxx)'],
+      ],
+    }],
+    ['OS=="linux" and target_arch=="arm" and host_arch!="arm" and chromeos==0 and clang==0', {
+      # Set default ARM cross tools on linux.  These can be overridden
+      # using CC,CXX,CC.host and CXX.host environment variables.
+      'make_global_settings': [
+        ['CC', '<!(which arm-linux-gnueabihf-gcc)'],
+        ['CXX', '<!(which arm-linux-gnueabihf-g++)'],
+        ['CC.host', '<(host_cc)'],
+        ['CXX.host', '<(host_cxx)'],
+      ],
+    }],
+    ['use_goma==1', {
+      'make_global_settings': [
+       ['CC_wrapper', '<(gomadir)/gomacc'],
+       ['CXX_wrapper', '<(gomadir)/gomacc'],
+       ['CC.host_wrapper', '<(gomadir)/gomacc'],
+       ['CXX.host_wrapper', '<(gomadir)/gomacc'],
+      ],
+    }],
+    ['use_lto==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'cflags': [
+              '-flto',
+            ],
+            'xcode_settings': {
+              'LLVM_LTO': 'YES',
+            },
+          }],
+          # Work-around for http://openradar.appspot.com/20356002
+          ['_toolset=="target" and _type!="static_library"', {
+            'xcode_settings': {
+              'OTHER_LDFLAGS': [
+                '-Wl,-all_load',
+              ],
+            },
+          }],
+        ],
+      },
+    }],
+    ['use_lto==1 and clang==0', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'cflags': [
+              '-ffat-lto-objects',
+            ],
+          }],
+        ],
+      },
+    }],
+    ['use_lto==1 and clang==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'arflags': [
+              '--plugin', '../../<(make_clang_dir)/lib/LLVMgold.so',
+            ],
+            'cflags': [
+              '-fwhole-program-vtables',
+            ],
+            'ldflags': [
+              '-fwhole-program-vtables',
+            ],
+          }],
+        ],
+        'msvs_settings': {
+          'VCCLCompilerTool': {
+            'AdditionalOptions': [
+              # TODO(pcc): Add LTO support to clang-cl driver and use it here.
+              '-Xclang',
+              '-emit-llvm-bc',
+            ],
+          },
+        },
+      },
+    }],
+    # Apply a lower LTO optimization level as the default is too slow.
+    ['use_lto==1 and clang==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'ldflags': [
+              '-Wl,--plugin-opt,O1',
+              # Allows the linker to apply ICF to the LTO object file. Also, when
+              # targeting ARM, wWithout this flag, LTO produces a .text section
+              # that is larger than the maximum call displacement, preventing the
+              # linker from relocating calls (http://llvm.org/PR22999).
+              '-Wl,--plugin-opt,-function-sections',
+            ],
+          }],
+          ['_toolset=="target" and _type!="static_library"', {
+            'xcode_settings':  {
+              'OTHER_LDFLAGS': [
+                '-Wl,-mllvm,-O1',
+              ],
+            },
+          }],
+        ],
+        'msvs_settings': {
+          'VCLinkerTool': {
+            'AdditionalOptions': [
+              '/opt:lldlto=1',
+            ],
+          },
+        },
+      },
+    }],
+    ['(use_lto==1 or use_lto_o2==1) and clang==0', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'ldflags': [
+              '-flto=32',
+            ],
+          }],
+        ],
+      },
+    }],
+    ['(use_lto==1 or use_lto_o2==1) and clang==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'ldflags': [
+              '-flto',
+            ],
+          }],
+        ],
+      },
+    }],
+    ['cfi_diag==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'cflags': [
+              '-fno-sanitize-trap=cfi',
+              '-fsanitize-recover=cfi',
+            ],
+            'cflags_cc!': [
+              '-fno-rtti',
+            ],
+            'cflags!': [
+              '-fno-rtti',
+            ],
+            'ldflags': [
+              '-fno-sanitize-trap=cfi',
+              '-fsanitize-recover=cfi',
+            ],
+            'xcode_settings': {
+              'OTHER_CFLAGS': [
+                '-fno-sanitize-trap=cfi',
+                '-fsanitize-recover=cfi',
+              ],
+            },
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  '-fno-sanitize-trap=cfi',
+                  '-fsanitize-recover=cfi',
+                ],
+              },
+            },
+          }],
+          ['_toolset=="target" and _type!="static_library"', {
+            'xcode_settings':  {
+              'OTHER_LDFLAGS': [
+                '-fno-sanitize-trap=cfi',
+                '-fsanitize-recover=cfi',
+              ],
+            },
+          }],
+        ],
+      },
+    }],
+    ['cfi_vptr==1 and cfi_diag==0', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'defines': [
+              'CFI_ENFORCEMENT',
+            ],
+          }],
+        ],
+      },
+    }],
+    ['cfi_vptr==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'cflags': [
+              '-fsanitize=cfi-vcall',
+              '-fsanitize-blacklist=<(cfi_blacklist)',
+            ],
+            'ldflags': [
+              '-fsanitize=cfi-vcall',
+              '-fsanitize=cfi-derived-cast',
+              '-fsanitize=cfi-unrelated-cast',
+            ],
+            'xcode_settings': {
+              'OTHER_CFLAGS': [
+                '-fsanitize=cfi-vcall',
+                '-fsanitize-blacklist=<(cfi_blacklist)',
+              ],
+            },
+          }],
+          ['_toolset=="target" and _type!="static_library"', {
+            'xcode_settings':  {
+              'OTHER_LDFLAGS': [
+                '-fsanitize=cfi-vcall',
+              ],
+            },
+          }],
+        ],
+      },
+    }],
+    ['cfi_vptr==1 and cfi_cast==1', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'cflags': [
+              '-fsanitize=cfi-derived-cast',
+              '-fsanitize=cfi-unrelated-cast',
+            ],
+            'ldflags': [
+              '-fsanitize=cfi-derived-cast',
+              '-fsanitize=cfi-unrelated-cast',
+            ],
+            'xcode_settings': {
+              'OTHER_CFLAGS': [
+                '-fsanitize=cfi-derived-cast',
+                '-fsanitize=cfi-unrelated-cast',
+              ],
+            },
+          }],
+          ['_toolset=="target" and _type!="static_library"', {
+            'xcode_settings':  {
+              'OTHER_LDFLAGS': [
+                '-fsanitize=cfi-derived-cast',
+                '-fsanitize=cfi-unrelated-cast',
+              ],
+            },
+          }],
+        ],
+      },
+    }],
+    ['cfi_vptr==1 and OS=="win"', {
+      'target_defaults': {
+        'target_conditions': [
+          ['_toolset=="target"', {
+            'msvs_settings': {
+              'VCCLCompilerTool': {
+                'AdditionalOptions': [
+                  # TODO(pcc): Use regular -fsanitize=* flags here once clang-cl
+                  # supports LTO.
+                  '-Xclang',
+                  '-fsanitize=cfi-vcall',
+                  '-Xclang',
+                  '-fsanitize=cfi-derived-cast',
+                  '-Xclang',
+                  '-fsanitize=cfi-unrelated-cast',
+                  '-Xclang',
+                  '-fsanitize-trap=cfi-vcall',
+                  '-Xclang',
+                  '-fsanitize-trap=cfi-derived-cast',
+                  '-Xclang',
+                  '-fsanitize-trap=cfi-unrelated-cast',
+                  '-Xclang',
+                  '-fsanitize-blacklist=<(cfi_blacklist)',
+                  '-Xclang',
+                  '-fsanitize-blacklist=../../<(make_clang_dir)/lib/clang/<!(python <(DEPTH)/tools/clang/scripts/update.py --print-clang-version)/cfi_blacklist.txt',
+                ],
+              },
+            },
+          }],
+        ],
+      },
+    }],
+  ],
+  'xcode_settings': {
+    # DON'T ADD ANYTHING NEW TO THIS BLOCK UNLESS YOU REALLY REALLY NEED IT!
+    # This block adds *project-wide* configuration settings to each project
+    # file.  It's almost always wrong to put things here.  Specify your
+    # custom xcode_settings in target_defaults to add them to targets instead.
+
+    'conditions': [
+      # In an Xcode Project Info window, the "Base SDK for All Configurations"
+      # setting sets the SDK on a project-wide basis. In order to get the
+      # configured SDK to show properly in the Xcode UI, SDKROOT must be set
+      # here at the project level.
+      ['OS=="mac"', {
+        'ARCHS': [ 'x86_64' ],
+        'conditions': [
+          ['mac_sdk_path==""', {
+            'SDKROOT': 'macosx<(mac_sdk)',  # -isysroot
+          }, {
+            'SDKROOT': '<(mac_sdk_path)',  # -isysroot
+          }],
+        ],
+      }],
+      ['OS=="ios"', {
+        # Target both iPhone and iPad.
+        'TARGETED_DEVICE_FAMILY': '1,2',
+        'conditions': [
+          ['ios_sdk_path==""', {
+            'SDKROOT': 'iphoneos<(ios_sdk)',  # -isysroot
+          }, {
+            'SDKROOT': '<(ios_sdk_path)',  # -isysroot
+          }],
+        ],
+      }],
+    ],
+
+    # The Xcode generator will look for an xcode_settings section at the root
+    # of each dict and use it to apply settings on a file-wide basis.  Most
+    # settings should not be here, they should be in target-specific
+    # xcode_settings sections, or better yet, should use non-Xcode-specific
+    # settings in target dicts.  SYMROOT is a special case, because many other
+    # Xcode variables depend on it, including variables such as
+    # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
+    # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
+    # files to appear (when present) in the UI as actual files and not red
+    # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
+    # and therefore SYMROOT, needs to be set at the project level.
+    'SYMROOT': '<(DEPTH)/xcodebuild',
+  },
+}