Reland: Add Stop() to AudioDecoder. (https://codereview.chromium.org/126793002/)

media/filters/opus_audio_decoder.h

Index: media/filters/opus_audio_decoder.h
diff --git a/media/filters/opus_audio_decoder.h b/media/filters/opus_audio_decoder.h
index d5eb595cd1045c6558831ebc84674ca147f1a2f1..2faacedd83b34856a815b3525e94d319e12d0319 100644
--- a/media/filters/opus_audio_decoder.h
+++ b/media/filters/opus_audio_decoder.h
@@ -40,14 +40,17 @@ class MEDIA_EXPORT OpusAudioDecoder : public AudioDecoder {
   virtual ChannelLayout channel_layout() OVERRIDE;
   virtual int samples_per_second() OVERRIDE;
   virtual void Reset(const base::Closure& closure) OVERRIDE;
+  virtual void Stop(const base::Closure& closure) OVERRIDE;
 
  private:
+  void DoReset();
+  void DoStop();
+
   // Reads from the demuxer stream with corresponding callback method.
   void ReadFromDemuxerStream();
   void BufferReady(DemuxerStream::Status status,
                    const scoped_refptr<DecoderBuffer>& input);
 
-
   bool ConfigureDecoder();
   void CloseDecoder();
   void ResetTimestampState();
@@ -73,6 +76,8 @@ class MEDIA_EXPORT OpusAudioDecoder : public AudioDecoder {
   base::TimeDelta last_input_timestamp_;
 
   ReadCB read_cb_;
+  base::Closure reset_cb_;
+  base::Closure stop_cb_;
 
   // Number of frames to be discarded from the start of the packet. This value
   // is respected for all packets except for the first one in the stream. For