Set the AudioManager factory before the browser main loop.

chromecast/browser/cast_browser_main_parts.cc

Index: chromecast/browser/cast_browser_main_parts.cc
diff --git a/chromecast/browser/cast_browser_main_parts.cc b/chromecast/browser/cast_browser_main_parts.cc
index 1c0ca15f666b4b12fd6f83723ce5ef0a60597811..a4a8cea125cc3d11786a449c3e82fa3eb85a6263 100644
--- a/chromecast/browser/cast_browser_main_parts.cc
+++ b/chromecast/browser/cast_browser_main_parts.cc
@@ -140,6 +140,14 @@ void DeregisterKillOnAlarm() {
 }  // namespace
 
 namespace chromecast {
+
+namespace media {
+// Forward declaration of setter for audio manager factory. This method should
+// call ::media::AudioManager::SetAudioManagerFactory to provide a platform
+// implmentation of AudioManager.
+void SetPlatformAudioManagerFactory();

[gunsch, 2015/04/30 15:50:38]

This interface probably lives better somewhere like CastContentBrowserClient,
such as:

::media::AudioManagerFactory*
CastContentBrowserClient::GetPlatformAudioManagerFactory()

+}
+
 namespace shell {
 
 namespace {
@@ -212,6 +220,9 @@ void CastBrowserMainParts::PreMainMessageLoopStart() {
   // Net/DNS metrics.
   metrics::PreregisterAllGroupedHistograms();
 
+  // Set the platform's implementation of AudioManager factory.
+  ::chromecast::media::SetPlatformAudioManagerFactory();
+
 #if defined(OS_ANDROID)
   net::NetworkChangeNotifier::SetFactory(
       new net::NetworkChangeNotifierFactoryAndroid());