Use --icf=all for Linux64 too.

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.
@@ skipping 671 matching lines @@
       # 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.
       #
       # On Android, 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,
 
       # Control Flow Integrity for virtual calls and casts.
       # See http://clang.llvm.org/docs/ControlFlowIntegrity.html
       'cfi_vptr%': 0,
 
       'cfi_blacklist%': '<(PRODUCT_DIR)/../../tools/cfi/blacklist.txt',
 
       # Whether the entire browser uses toolkit-views on Mac instead of Cocoa.
@@ skipping 515 matching lines @@
     'native_memory_pressure_signals%': '<(native_memory_pressure_signals)',
     'enable_mdns%' : '<(enable_mdns)',
     'enable_service_discovery%' : '<(enable_service_discovery)',
     'enable_wifi_bootstrapping%': '<(enable_wifi_bootstrapping)',
     '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_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)',
     'enable_webvr%': '<(enable_webvr)',
 
     # Turns on compiler optimizations in V8 in Debug build.
@@ skipping 961 matching lines @@
         'clang_chrome_plugins_flags%':
           '<(clang_dynlib_flags)'
           '-Xclang -add-plugin -Xclang find-bad-constructs <(clang_plugin_args)',
       }],
       ['asan==1 or msan==1 or lsan==1 or tsan==1', {
         'clang%': 1,
         'use_allocator%': 'none',
         'use_sanitizer_options%': 1,
       }],
 
-      # Allowed level of identical code folding in the gold linker.
-      ['OS=="linux" and target_arch=="x64"', {
-        # --icf=safe disables much more folding on x86_64 than elsewhere, see
-        # http://crbug.com/492177.  Turning it on saves over 12 MB of binary
-        # size, but it seems to regress cold startup time by over a second
-        # (see http://crbug.com/492809).
-        # TODO(thakis): Check if disabling ICF would inmprove android cold start
-        # times by several seconds too.
-        'gold_icf_level%': 'safe',
-      }, {
-        'gold_icf_level%': 'all',
-      }],
-
       ['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,
@@ skipping 3979 matching lines @@
     # 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',
   },
 }