Detect AudioInputStream muting and propagate to MediaStreamAudioSource.

content/browser/renderer_host/media/audio_input_renderer_host.h

Index: content/browser/renderer_host/media/audio_input_renderer_host.h
diff --git a/content/browser/renderer_host/media/audio_input_renderer_host.h b/content/browser/renderer_host/media/audio_input_renderer_host.h
index d9a2d0a647197a01036f4c4a1fccb01c0d000114..47682e3195de96510127c3e98048eb56cd8f426d 100644
--- a/content/browser/renderer_host/media/audio_input_renderer_host.h
+++ b/content/browser/renderer_host/media/audio_input_renderer_host.h
@@ -115,6 +115,7 @@ class CONTENT_EXPORT AudioInputRendererHost
                media::AudioInputController::ErrorCode error_code) override;
   void OnLog(media::AudioInputController* controller,
              const std::string& message) override;
+  void OnMuted(media::AudioInputController* controller, bool is_muted) override;
 
   // Sets the PID renderer. This is used for constructing the debug recording
   // filename.
@@ -177,6 +178,10 @@ class CONTENT_EXPORT AudioInputRendererHost
   void DoLog(media::AudioInputController* controller,
              const std::string& message);
 
+  // Notify renderer of a change to a stream's muted state.
+  void DoNotifyMutedState(media::AudioInputController* controller,
+                          bool is_muted);
+
   // Send an error message to the renderer.
   void SendErrorMessage(int stream_id, ErrorCode error_code);