[TO M50] Enable implicit signalling for HE AAC v1 & v2 in ADTS.

media/base/audio_buffer.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 MEDIA_BASE_AUDIO_BUFFER_H_
 #define MEDIA_BASE_AUDIO_BUFFER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 60 matching lines @@
       int channel_count,
       int sample_rate,
       int frame_count,
       const base::TimeDelta timestamp);
 
   // Create a AudioBuffer indicating we've reached end of stream.
   // Calling any method other than end_of_stream() on the resulting buffer
   // is disallowed.
   static scoped_refptr<AudioBuffer> CreateEOSBuffer();
 
+  // Update sample rate and computed duration.
+  // TODO(chcunningham): Remove this upon patching FFmpeg's AAC decoder to
+  // provide the correct sample rate at the boundary of an implicit config
+  // change.
+  void AdjustSampleRate(int sample_rate);
+
   // Copy frames into |dest|. |frames_to_copy| is the number of frames to copy.
   // |source_frame_offset| specifies how many frames in the buffer to skip
   // first. |dest_frame_offset| is the frame offset in |dest|. The frames are
   // converted from their source format into planar float32 data (which is all
   // that AudioBus handles).
   void ReadFrames(int frames_to_copy,
                   int source_frame_offset,
                   int dest_frame_offset,
                   AudioBus* dest);
 
@@ skipping 70 matching lines @@
               int frame_count,
               bool create_buffer,
               const uint8_t* const* data,
               const base::TimeDelta timestamp);
 
   virtual ~AudioBuffer();
 
   const SampleFormat sample_format_;
   const ChannelLayout channel_layout_;
   const int channel_count_;
-  const int sample_rate_;
+  int sample_rate_;
   int adjusted_frame_count_;
   int trim_start_;
   const bool end_of_stream_;
   base::TimeDelta timestamp_;
   base::TimeDelta duration_;
 
   // Contiguous block of channel data.
   scoped_ptr<uint8_t, base::AlignedFreeDeleter> data_;
   size_t data_size_;
 
   // For planar data, points to each channels data.
   std::vector<uint8_t*> channel_data_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AudioBuffer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_BUFFER_H_