[WIP] Implement notification sound loader

content/content_child.gypi

 # Copyright 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.
 
 {
   'dependencies': [
     '../base/base.gyp:base',
     '../components/mime_util/mime_util.gyp:mime_util',
     '../components/tracing.gyp:tracing',
     '../components/webcrypto/webcrypto.gyp:webcrypto',
@@ skipping 114 matching lines @@
       'child/navigator_connect/service_port_provider.cc',
       'child/navigator_connect/service_port_provider.h',
       'child/notifications/notification_data_conversions.cc',
       'child/notifications/notification_data_conversions.h',
       'child/notifications/notification_dispatcher.cc',
       'child/notifications/notification_dispatcher.h',
       'child/notifications/notification_image_loader.cc',
       'child/notifications/notification_image_loader.h',
       'child/notifications/notification_manager.cc',
       'child/notifications/notification_manager.h',
+      'child/notifications/notification_sound_loader.cc',
+      'child/notifications/notification_sound_loader.h',
       'child/notifications/pending_notifications_tracker.cc',
       'child/notifications/pending_notifications_tracker.h',
       'child/npapi/np_channel_base.cc',
       'child/npapi/np_channel_base.h',
       'child/npapi/npobject_base.h',
       'child/npapi/npobject_proxy.cc',
       'child/npapi/npobject_proxy.h',
       'child/npapi/npobject_stub.cc',
       'child/npapi/npobject_stub.h',
       'child/npapi/npobject_util.cc',
@@ skipping 191 matching lines @@
         'child/npapi/webplugin_delegate_impl_mac.mm',
       ],
     }],
     ['OS=="win"', {
       'sources!': [
         'child/npapi/webplugin_delegate_impl_aura.cc',
       ],
     }],
   ],
 }