Part 1: Plumb render view ID to render host

content/renderer/media/audio_renderer_mixer_manager.cc

Index: content/renderer/media/audio_renderer_mixer_manager.cc
diff --git a/content/renderer/media/audio_renderer_mixer_manager.cc b/content/renderer/media/audio_renderer_mixer_manager.cc
index 411ae8b430a346e647f51e447faeaee20bdc7694..6d45016aae93d65a33ef3a077a270203bb285af9 100644
--- a/content/renderer/media/audio_renderer_mixer_manager.cc
+++ b/content/renderer/media/audio_renderer_mixer_manager.cc
@@ -22,15 +22,19 @@ AudioRendererMixerManager::~AudioRendererMixerManager() {
   DCHECK(mixers_.empty());
 }
 
-media::AudioRendererMixerInput* AudioRendererMixerManager::CreateInput() {
+media::AudioRendererMixerInput* AudioRendererMixerManager::CreateInput(
+    int render_view_id) {
   return new media::AudioRendererMixerInput(
       base::Bind(
-          &AudioRendererMixerManager::GetMixer, base::Unretained(this)),
+          &AudioRendererMixerManager::GetMixer,
+          base::Unretained(this),
+          render_view_id),
       base::Bind(
           &AudioRendererMixerManager::RemoveMixer, base::Unretained(this)));
 }
 
 media::AudioRendererMixer* AudioRendererMixerManager::GetMixer(
+    int render_view_id,
     const media::AudioParameters& params) {
   base::AutoLock auto_lock(mixers_lock_);
 
@@ -48,7 +52,9 @@ media::AudioRendererMixer* AudioRendererMixerManager::GetMixer(
       hardware_sample_rate_, 16, hardware_buffer_size_);
 
   media::AudioRendererMixer* mixer = new media::AudioRendererMixer(
-      params, output_params, AudioDeviceFactory::NewOutputDevice());
+      params,
+      output_params,
+      AudioDeviceFactory::NewOutputDevice(render_view_id));
 
   AudioRendererMixerReference mixer_reference = { mixer, 1 };
   mixers_[params] = mixer_reference;