Add garbage collection for shared extensions on Chrome OS

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.
 
 {
   'targets': [
     {
       'target_name': 'browser_extensions',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 700 matching lines @@
         'browser/extensions/extension_error_controller.cc',
         'browser/extensions/extension_error_controller.h',
         'browser/extensions/extension_error_reporter.cc',
         'browser/extensions/extension_error_reporter.h',
         'browser/extensions/extension_error_ui.cc',
         'browser/extensions/extension_error_ui.h',
         'browser/extensions/extension_error_ui_default.cc',
         'browser/extensions/extension_error_ui_default.h',
         'browser/extensions/extension_garbage_collector.cc',
         'browser/extensions/extension_garbage_collector.h',
+        'browser/extensions/extension_garbage_collector_chromeos.cc',
+        'browser/extensions/extension_garbage_collector_chromeos.h',
         'browser/extensions/extension_garbage_collector_factory.cc',
         'browser/extensions/extension_garbage_collector_factory.h',
         'browser/extensions/extension_gcm_app_handler.cc',
         'browser/extensions/extension_gcm_app_handler.h',
         'browser/extensions/extension_icon_image.cc',
         'browser/extensions/extension_icon_image.h',
         'browser/extensions/extension_icon_manager.cc',
         'browser/extensions/extension_icon_manager.h',
         'browser/extensions/extension_infobar_delegate.cc',
         'browser/extensions/extension_infobar_delegate.h',
@@ skipping 513 matching lines @@
       'type': 'static_library',
       'sources': [ 'browser/extensions/api/cast_channel/cast_channel.proto' ],
       'variables': {
           'proto_in_dir': 'browser/extensions/api/cast_channel',
           'proto_out_dir': 'chrome/browser/extensions/api/cast_channel',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],  # 'conditions'
 }