Fix media timeline so that thumb never exceeds buffered data

media/filters/audio_renderer_base.h

 // Copyright (c) 2011 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.
 
 // AudioRendererBase takes care of the tricky queuing work and provides simple
 // methods for subclasses to peek and poke at audio data.  In addition to
 // AudioRenderer interface methods this classes doesn't implement, subclasses
 // must also implement the following methods:
 //   OnInitialized
 //   OnStop
@@ skipping 24 matching lines @@
   // Filter implementation.
   virtual void Play(const base::Closure& callback) OVERRIDE;
   virtual void Pause(const base::Closure& callback) OVERRIDE;
   virtual void Stop(const base::Closure& callback) OVERRIDE;
 
   virtual void Seek(base::TimeDelta time, const FilterStatusCB& cb) OVERRIDE;
 
   // AudioRenderer implementation.
   virtual void Initialize(AudioDecoder* decoder,
                           const base::Closure& init_callback,
-                          const base::Closure& underflow_callback) OVERRIDE;
+                          const base::Closure& underflow_callback,
+                          const AudioTimeCB& audio_time_cb) OVERRIDE;
   virtual bool HasEnded() OVERRIDE;
   virtual void ResumeAfterUnderflow(bool buffer_more_audio) OVERRIDE;
 
  protected:
   // Subclasses should return true if they were able to initialize, false
   // otherwise.
   virtual bool OnInitialize(int bits_per_channel,
                             ChannelLayout channel_layout,
                             int sample_rate) = 0;
 
@@ skipping 74 matching lines @@
   // Audio time at end of last call to FillBuffer().
   // TODO(ralphl): Update this value after seeking.
   base::TimeDelta last_fill_buffer_time_;
 
   // Filter callbacks.
   base::Closure pause_callback_;
   FilterStatusCB seek_cb_;
 
   base::Closure underflow_callback_;
 
+  AudioTimeCB audio_time_cb_;
+
   base::TimeDelta seek_timestamp_;
 
   AudioDecoder::ReadCB read_cb_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererBase);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_AUDIO_RENDERER_BASE_H_