Introduce AudioHardwareConfig for renderer side audio device info.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index d9baea00cb95471840b09fce25f6193420800a58..35707ede150821c81b5cd32ed7fcc7e37b887b91 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -55,13 +55,13 @@
 #include "content/renderer/gpu/compositor_thread.h"
 #include "content/renderer/gpu/compositor_output_surface.h"
 #include "content/renderer/gpu/gpu_benchmarking_extension.h"
-#include "content/renderer/media/audio_hardware.h"
 #include "content/renderer/media/audio_input_message_filter.h"
 #include "content/renderer/media/audio_message_filter.h"
 #include "content/renderer/media/audio_renderer_mixer_manager.h"
 #include "content/renderer/media/media_stream_center.h"
 #include "content/renderer/media/media_stream_dependency_factory.h"
 #include "content/renderer/media/peer_connection_tracker.h"
+#include "content/renderer/media/renderer_audio_hardware_config.h"
 #include "content/renderer/media/video_capture_impl_manager.h"
 #include "content/renderer/media/video_capture_message_filter.h"
 #include "content/renderer/p2p/socket_dispatcher.h"
@@ -897,13 +897,19 @@ RenderThreadImpl::GetGpuVDAContext3D() {
 AudioRendererMixerManager* RenderThreadImpl::GetAudioRendererMixerManager() {
   if (!audio_renderer_mixer_manager_.get()) {
     audio_renderer_mixer_manager_.reset(new AudioRendererMixerManager(
-        GetAudioOutputSampleRate(),
-        GetAudioOutputBufferSize()));
+        GetAudioHardwareConfig()));
   }
 
   return audio_renderer_mixer_manager_.get();
 }
 
+RendererAudioHardwareConfig* RenderThreadImpl::GetAudioHardwareConfig() {
+  if (!audio_hardware_config_)

[miu, 2013/01/29 04:55:43]

Nice.  I was wondering whether a render process had to block on start-up when
audio is never used.

+    audio_hardware_config_.reset(new RendererAudioHardwareConfig());
+
+  return audio_hardware_config_.get();
+}
+
 #if defined(OS_WIN)
 void RenderThreadImpl::PreCacheFontCharacters(const LOGFONT& log_font,
                                               const string16& str) {