Adds a field trial to control Web API kill switches.

chrome/chrome_browser.gypi

 # Copyright 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.
 
 {
   'variables': {
     # All .cc, .h, .m, and .mm files under browser except for:
     # * tests and mocks.
     # * code below browser/chromeos
     # * code below browser/extensions
@@ skipping 2066 matching lines @@
       'browser/permissions/permission_manager.cc',
       'browser/permissions/permission_manager.h',
       'browser/permissions/permission_manager_factory.cc',
       'browser/permissions/permission_manager_factory.h',
       'browser/permissions/permission_queue_controller.cc',
       'browser/permissions/permission_queue_controller.h',
       'browser/permissions/permission_request_id.cc',
       'browser/permissions/permission_request_id.h',
       'browser/permissions/permission_update_infobar_delegate_android.cc',
       'browser/permissions/permission_update_infobar_delegate_android.h',
+      'browser/permissions/permission_util.cc',
+      'browser/permissions/permission_util.h',
     ],
     # See also the plugin_installation_sources list below.
     'chrome_browser_plugins_sources': [
       'browser/browsing_data/browsing_data_flash_lso_helper.cc',
       'browser/browsing_data/browsing_data_flash_lso_helper.h',
       'browser/component_updater/flash_component_installer.h',
       'browser/component_updater/pepper_flash_component_installer.cc',
       'browser/metrics/plugin_metrics_provider.cc',
       'browser/metrics/plugin_metrics_provider.h',
       'browser/pepper_broker_infobar_delegate.cc',
@@ skipping 2013 matching lines @@
             '../components/components.gyp:omnibox_browser',
             '../components/components.gyp:rlz',
             '../components/components.gyp:search_engines',
             '../rlz/rlz.gyp:rlz_lib',
           ],
         },
       ],
     }],
   ],
 }