Build 64-bit binaries by default when compiling for iOS

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 230 matching lines @@
 
           # Set default gomadir.
           ['OS=="win"', {
             'gomadir': 'c:\\goma\\goma-win',
           }, {
             'gomadir': '<!(/bin/echo -n ${HOME}/goma)',
           }],
 
           # Set the default "target_subarch" on iOS. Valid values are "arm32",
           # "arm64" and "both" (meaning a fat binary).
-          #
-          # TODO(sdefresne): change the default from "arm32" to "both" for
-          # "target_subarch" once http://crbug.com/339477 is fixed.
-          #
-          # TODO(sdefresne): set the "target_arch" to "arm" once compilation
-          # of skia has been fixed for simulator. http://crbug.com/342377
           ['OS=="ios"', {
-            'target_subarch%': 'arm32',
+            'target_subarch%': 'arm64',
           }],
 
           # Set arch variants for MIPS platforms.
           ['target_arch=="mips64el"', {
             'conditions': [
               ['OS=="android"', {
                 'mips_arch_variant%': 'r6',
               }, {
                 'mips_arch_variant%': 'r2',
               }],
@@ skipping 5754 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',
   },
 }