Lazily initialize MessageLoop for faster thread startup

media/audio/audio_manager_base.cc

Index: media/audio/audio_manager_base.cc
diff --git a/media/audio/audio_manager_base.cc b/media/audio/audio_manager_base.cc
index edaabf4c22771e71ef38a1fba14f4969e587141e..445972462c5e27f948cc1acf8aaff28aa7473f68 100644
--- a/media/audio/audio_manager_base.cc
+++ b/media/audio/audio_manager_base.cc
@@ -95,7 +95,14 @@ AudioManagerBase::AudioManagerBase(AudioLogFactory* audio_log_factory)
   }
 #endif
 
+#if defined(OS_WIN)
+  // We check COM initializer status right after calling this, so wait here

[DaleCurtis, 2015/03/18 22:04:28]

Ah dang, I was hoping this one would be one we could remove since it's on the
BrowserMainLoop startup path.

[kinuko, 2015/03/19 03:08:16]

I haven't taken a deeper look but I guess we can probably fix this with some
refactoring in audio code, but so it'll need to be done in a separate bug/CL.

[kinuko, 2015/03/19 03:08:16]

I guess we can probably fix this but with some refactoring in audio code. We'll
need another bug/CL for this anyway.

+  // until we finish audio thread initialization (where we also run COM
+  // initializer).
+  CHECK(audio_thread_.StartAndWait());
+#else
   CHECK(audio_thread_.Start());
+#endif
   task_runner_ = audio_thread_.message_loop_proxy();
 }