New build flag system, convert Google Now flag

chrome/chrome_browser_extensions.gypi

 # Copyright (c) 2013 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.
 
 {
   'variables': {
     'chrome_browser_extensions_chromeos_sources': [
       'browser/extensions/api/cast_devices_private/cast_devices_private_api.cc',
       'browser/extensions/api/cast_devices_private/cast_devices_private_api.h',
       'browser/extensions/api/certificate_provider/certificate_provider_api.cc',
@@ skipping 938 matching lines @@
       'target_name': 'browser_extensions',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
       # Since browser and browser_extensions actually depend on each other,
       # we must omit the dependency from browser_extensions to browser.
       # However, this means browser_extensions and browser should more or less
       # have the same dependencies. Once browser_extensions is untangled from
       # browser, then we can clean up these dependencies.
       'dependencies': [
         'browser/extensions/api/api_registration.gyp:chrome_api_registration',
+        'chrome_common_features',
         'chrome_resources.gyp:chrome_extra_resources',
         'chrome_resources.gyp:chrome_resources',
         'chrome_resources.gyp:chrome_strings',
         'chrome_resources.gyp:platform_locale_settings',
         'chrome_resources.gyp:theme_resources',
         'common',
         'common/extensions/api/api.gyp:chrome_api',
         'debugger',
         'installer_util',
         'safe_browsing_proto',
@@ skipping 177 matching lines @@
           ],
         }, {  # use_brlapi==0
           'sources': [
             'browser/extensions/api/braille_display_private/braille_controller_stub.cc',
           ],
         }],
       ],
     },
   ],
 }