Set the AudioManager factory before the browser main loop.

chromecast/chromecast.gyp

 # Copyright 2014 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': {
     'android_support_v13_target%':
         '../third_party/android_tools/android_tools.gyp:android_support_v13_javalib',
     'cast_build_release': 'internal/build/cast_build_release',
     'cast_is_debug_build%': 0,
@@ skipping 270 matching lines @@
       'conditions': [
         ['chromecast_branding=="Chrome"', {
           'dependencies': [
             'internal/chromecast_internal.gyp:cast_shell_internal',
           ],
         }, {
           'sources': [
             'browser/cast_content_browser_client_simple.cc',
             'browser/cast_network_delegate_simple.cc',
             'browser/devtools/remote_debugging_server_simple.cc',
+            'browser/media/audio_manager_factory_simple.cc',
             'browser/metrics/platform_metrics_providers_simple.cc',
             'browser/pref_service_helper_simple.cc',
             'common/platform_client_auth_simple.cc',
             'renderer/cast_content_renderer_client_simple.cc',
             'renderer/key_systems_cast_simple.cc',
           ],
           'conditions': [
             ['OS=="android"', {
               'sources': [
                 'browser/service/cast_service_android.cc',
@@ skipping 329 matching lines @@
           'sources': [
             'graphics/cast_egl_platform_default.cc',
             'graphics/graphics_properties_default.cc',
             'graphics/osd_plane_default.cc'
           ],
         }
       ]
     }],
   ],  # end of conditions
 }