[Android] Roll to NDK r12b.

build/config/android/config.gni

 # Copyright 2014 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.
 
 # This file contains common system config stuff for the Android build.
 
 if (is_android) {
   assert(rebase_path("//", root_build_dir) == "../../",
          "Android output directory must be nested 2 levels within src/ (" +
              "e.g.: out-gn/Debug). http://crbug.com/412935")
 
   import("//build_overrides/build.gni")
 
   has_chrome_android_internal =
       exec_script("//build/dir_exists.py",
                   [ rebase_path("//clank", root_build_dir) ],
                   "string") == "True"
 
   if (has_chrome_android_internal) {
     import("//clank/config.gni")
   }
 
   if (!defined(extra_chrome_shared_library_configs)) {
     extra_chrome_shared_library_configs = []
   }
 
   if (!defined(default_android_ndk_root)) {
     default_android_ndk_root = "//third_party/android_tools/ndk"
-    default_android_ndk_version = "r10e"
-    default_android_ndk_major_version = "10"
+    default_android_ndk_version = "r12b"
+    default_android_ndk_major_version = "12"
   } else {
     assert(defined(default_android_ndk_version))
     assert(defined(default_android_ndk_major_version))
   }
 
   if (!defined(default_android_sdk_root)) {
     default_android_sdk_root = "//third_party/android_tools/sdk"
     default_android_sdk_version = "23"
     default_android_sdk_build_tools_version = "23.0.1"
   }
@@ skipping 162 matching lines @@
   x86_64_android_sysroot_subdir =
       "platforms/android-${_android64_api_level}/arch-x86_64"
   arm64_android_sysroot_subdir =
       "platforms/android-${_android64_api_level}/arch-arm64"
   mips64_android_sysroot_subdir =
       "platforms/android-${_android64_api_level}/arch-mips64"
 
   # Toolchain root directory for each build. The actual binaries are inside
   # a "bin" directory inside of these.
   _android_toolchain_version = "4.9"
+  _android_toolchain_detailed_version = "4.9.x"
   x86_android_toolchain_root = "$android_ndk_root/toolchains/x86-${_android_toolchain_version}/prebuilt/${android_host_os}-${android_host_arch}"
   arm_android_toolchain_root = "$android_ndk_root/toolchains/arm-linux-androideabi-${_android_toolchain_version}/prebuilt/${android_host_os}-${android_host_arch}"
   mips_android_toolchain_root = "$android_ndk_root/toolchains/mipsel-linux-android-${_android_toolchain_version}/prebuilt/${android_host_os}-${android_host_arch}"
   x86_64_android_toolchain_root = "$android_ndk_root/toolchains/x86_64-${_android_toolchain_version}/prebuilt/${android_host_os}-${android_host_arch}"
   arm64_android_toolchain_root = "$android_ndk_root/toolchains/aarch64-linux-android-${_android_toolchain_version}/prebuilt/${android_host_os}-${android_host_arch}"
   mips64_android_toolchain_root = "$android_ndk_root/toolchains/mips64el-linux-android-${_android_toolchain_version}/prebuilt/${android_host_os}-${android_host_arch}"
 
   # Location of libgcc. This is only needed for the current GN toolchain, so we
   # only need to define the current one, rather than one for every platform
   # like the toolchain roots.
   if (current_cpu == "x86") {
     android_prebuilt_arch = "android-x86"
     _binary_prefix = "i686-linux-android"
     android_toolchain_root = "$x86_android_toolchain_root"
-    android_libgcc_file = "$android_toolchain_root/lib/gcc/i686-linux-android/${_android_toolchain_version}/libgcc.a"
+    android_libgcc_file = "$android_toolchain_root/lib/gcc/i686-linux-android/${_android_toolchain_detailed_version}/libgcc.a"
   } else if (current_cpu == "arm") {
     android_prebuilt_arch = "android-arm"
     _binary_prefix = "arm-linux-androideabi"
     android_toolchain_root = "$arm_android_toolchain_root"
-    android_libgcc_file = "$android_toolchain_root/lib/gcc/arm-linux-androideabi/${_android_toolchain_version}/libgcc.a"
+    android_libgcc_file = "$android_toolchain_root/lib/gcc/arm-linux-androideabi/${_android_toolchain_detailed_version}/libgcc.a"
   } else if (current_cpu == "mipsel") {
     android_prebuilt_arch = "android-mips"
     _binary_prefix = "mipsel-linux-android"
     android_toolchain_root = "$mips_android_toolchain_root"
-    android_libgcc_file = "$android_toolchain_root/lib/gcc/mipsel-linux-android/${_android_toolchain_version}/libgcc.a"
+    android_libgcc_file = "$android_toolchain_root/lib/gcc/mipsel-linux-android/${_android_toolchain_detailed_version}/libgcc.a"
   } else if (current_cpu == "x64") {
     android_prebuilt_arch = "android-x86_64"
     _binary_prefix = "x86_64-linux-android"
     android_toolchain_root = "$x86_64_android_toolchain_root"
-    android_libgcc_file = "$android_toolchain_root/lib/gcc/x86_64-linux-android/${_android_toolchain_version}/libgcc.a"
+    android_libgcc_file = "$android_toolchain_root/lib/gcc/x86_64-linux-android/${_android_toolchain_detailed_version}/libgcc.a"
   } else if (current_cpu == "arm64") {
     android_prebuilt_arch = "android-arm64"
     _binary_prefix = "aarch64-linux-android"
     android_toolchain_root = "$arm64_android_toolchain_root"
-    android_libgcc_file = "$android_toolchain_root/lib/gcc/aarch64-linux-android/${_android_toolchain_version}/libgcc.a"
+    android_libgcc_file = "$android_toolchain_root/lib/gcc/aarch64-linux-android/${_android_toolchain_detailed_version}/libgcc.a"
   } else if (current_cpu == "mips64el") {
     android_prebuilt_arch = "android-mips64"
     _binary_prefix = "mips64el-linux-android"
     android_toolchain_root = "$mips64_android_toolchain_root"
-    android_libgcc_file = "$android_toolchain_root/lib/gcc/mips64el-linux-android/${_android_toolchain_version}/libgcc.a"
+    android_libgcc_file = "$android_toolchain_root/lib/gcc/mips64el-linux-android/${_android_toolchain_detailed_version}/libgcc.a"
   } else {
     assert(false, "Need android libgcc support for your target arch.")
   }
 
   android_tool_prefix = "$android_toolchain_root/bin/$_binary_prefix-"
   android_readelf = "${android_tool_prefix}readelf"
   android_objcopy = "${android_tool_prefix}objcopy"
   android_gdbserver =
       "$android_ndk_root/prebuilt/$android_prebuilt_arch/gdbserver/gdbserver"
 
@@ skipping 60 matching lines @@
           "//build/toolchain/android:${android_secondary_abi_cpu}"
     }
   }
 }
 
 declare_args() {
   # Enables used resource whitelist generation. Set for official builds only
   # as a large amount of build output is generated.
   enable_resource_whitelist_generation = is_android && is_official_build
 }