RefCounted types should not have public destructors, media/ and gpu/ edition

media/audio/null_audio_sink.h

Index: media/audio/null_audio_sink.h
diff --git a/media/audio/null_audio_sink.h b/media/audio/null_audio_sink.h
index 32245eb4cf34864efa9d7d091331c69cb144c6b5..69519c967e5b4e74ad0dd585e1c0b51626ba3347 100644
--- a/media/audio/null_audio_sink.h
+++ b/media/audio/null_audio_sink.h
@@ -24,7 +24,6 @@ class MEDIA_EXPORT NullAudioSink
     : NON_EXPORTED_BASE(public AudioRendererSink) {
  public:
   NullAudioSink();
-  virtual ~NullAudioSink();
 
   // AudioRendererSink implementation.
   virtual void Initialize(const AudioParameters& params,
@@ -37,6 +36,9 @@ class MEDIA_EXPORT NullAudioSink
   virtual bool SetVolume(double volume) OVERRIDE;
   virtual void GetVolume(double* volume) OVERRIDE;
 
+ protected:
+  virtual ~NullAudioSink();
+
  private:
   // Audio thread task that periodically calls FillBuffer() to consume
   // audio data.