Implement manifest icon downloader

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 555 matching lines @@
       'browser/mac/mac_startup_profiler.cc',
       'browser/mac/mac_startup_profiler.h',
       'browser/mac/master_prefs.h',
       'browser/mac/master_prefs.mm',
       'browser/mac/obsolete_system.cc',
       'browser/mac/obsolete_system.h',
       'browser/mac/relauncher.cc',
       'browser/mac/relauncher.h',
       'browser/mac/security_wrappers.cc',
       'browser/mac/security_wrappers.h',
+      'browser/manifest/manifest_icon_downloader.cc',
+      'browser/manifest/manifest_icon_downloader.h',
       'browser/manifest/manifest_icon_selector.cc',
       'browser/manifest/manifest_icon_selector.h',
       'browser/media/android/remote/record_cast_action.cc',
       'browser/media/android/remote/record_cast_action.h',
       'browser/media/android/remote/remote_media_player_bridge.cc',
       'browser/media/android/remote/remote_media_player_bridge.h',
       'browser/media/android/remote/remote_media_player_manager.cc',
       'browser/media/android/remote/remote_media_player_manager.h',
       'browser/media/android/router/media_router_android.cc',
       'browser/media/android/router/media_router_android.h',
@@ skipping 3526 matching lines @@
             '../components/components.gyp:omnibox_browser',
             '../components/components.gyp:rlz',
             '../components/components.gyp:search_engines',
             '../rlz/rlz.gyp:rlz_lib',
           ],
         },
       ],
     }],
   ],
 }