Part 2: Plumb render view ID to content::MediaObserver

content/browser/renderer_host/media/audio_renderer_host.h

Index: content/browser/renderer_host/media/audio_renderer_host.h
diff --git a/content/browser/renderer_host/media/audio_renderer_host.h b/content/browser/renderer_host/media/audio_renderer_host.h
index 491e6cecb5c09984f8679b308a45d984075deefc..b202ff0adb2b030bd78dd1c250c3eaf2499c062a 100644
--- a/content/browser/renderer_host/media/audio_renderer_host.h
+++ b/content/browser/renderer_host/media/audio_renderer_host.h
@@ -76,6 +76,9 @@ class CONTENT_EXPORT AudioRendererHost
     // The audio stream ID.
     int stream_id;
 
+    // The render view ID.
+    int render_view_id;
+
     // Shared memory for transmission of the audio data.
     base::SharedMemory shared_memory;
 
@@ -90,7 +93,8 @@ class CONTENT_EXPORT AudioRendererHost
   typedef std::map<int, AudioEntry*> AudioEntryMap;
 
   // Called from UI thread from the owner of this object.
-  AudioRendererHost(media::AudioManager* audio_manager,
+  AudioRendererHost(int render_process_id,
+                    media::AudioManager* audio_manager,
                     content::MediaObserver* media_observer);
 
   // content::BrowserMessageFilter implementation.
@@ -178,6 +182,8 @@ class CONTENT_EXPORT AudioRendererHost
   // event is received.
   AudioEntry* LookupByController(media::AudioOutputController* controller);
 
+  int render_process_id_;
+
   // A map of stream IDs to audio sources.
   AudioEntryMap audio_entries_;