Avoid hitting the thread check when WebRtcAudioRenderer is going away.

content/renderer/media/media_stream_audio_processor.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_H_
 
 #include "base/atomicops.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
@@ skipping 81 matching lines @@
 
  private:
   friend class MediaStreamAudioProcessorTest;
 
   class MediaStreamAudioConverter;
 
   // WebRtcPlayoutDataSource::Sink implementation.
   virtual void OnPlayoutData(media::AudioBus* audio_bus,
                              int sample_rate,
                              int audio_delay_milliseconds) OVERRIDE;
+  virtual void OnPlayoutDataSourceChanged() OVERRIDE;
 
   // webrtc::AudioProcessorInterface implementation.
   // This method is called on the libjingle thread.
   virtual void GetStats(AudioProcessorStats* stats) OVERRIDE;
 
   // Helper to initialize the WebRtc AudioProcessing.
   void InitializeAudioProcessingModule(
       const blink::WebMediaConstraints& constraints, int effects);
 
   // Helper to initialize the capture converter.
@@ skipping 60 matching lines @@
 
   // This flag is used to show the result of typing detection.
   // It can be accessed by the capture audio thread and by the libjingle thread
   // which calls GetStats().
   base::subtle::Atomic32 typing_detected_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_AUDIO_PROCESSOR_H_