Add MediaCodecAudioDecoder implementation

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 113 matching lines @@
   // Return the channel layout.
   ChannelLayout channel_layout() const { return channel_layout_; }
 
   base::TimeDelta timestamp() const { return timestamp_; }
   base::TimeDelta duration() const { return duration_; }
   void set_timestamp(base::TimeDelta timestamp) { timestamp_ = timestamp; }
 
   // If there's no data in this buffer, it represents end of stream.
   bool end_of_stream() const { return end_of_stream_; }
 
-  // Access to the raw buffer for ffmpeg to write directly to. Data for planar
-  // data is grouped by channel. There is only 1 entry for interleaved formats.
+  // Access to the raw buffer for ffmpeg and Android MediaCodec decoders to
+  // write directly to. For planar formats the vector elements correspond to
+  // the channels. For interleaved formats the resulting vector has exactly
+  // one element which contains the buffer pointer.
   const std::vector<uint8_t*>& channel_data() const { return channel_data_; }
 
+  // The size of allocated data memory block. For planar formats channels go
+  // sequentially in this block.
+  size_t data_size() const { return data_size_; }
+
  private:
   friend class base::RefCountedThreadSafe<AudioBuffer>;
 
   // mojo::TypeConverter added as a friend so that AudioBuffer can be
   // transferred across a mojo connection.
   friend struct mojo::TypeConverter<mojo::StructPtr<interfaces::AudioBuffer>,
                                     scoped_refptr<AudioBuffer>>;
 
   // Allocates aligned contiguous buffer to hold all channel data (1 block for
   // interleaved data, |channel_count| blocks for planar data), copies
@@ skipping 27 matching lines @@
 
   // 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_