Introduce AudioDecoderConfig to migrate away from GetAVStream().

media/base/filters.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.
 
 // Filters are connected in a strongly typed manner, with downstream filters
 // always reading data from upstream filters.  Upstream filters have no clue
 // who is actually reading from them, and return the results via callbacks.
 //
 //                         DemuxerStream(Video) <- VideoDecoder <- VideoRenderer
 // DataSource <- Demuxer <
@@ skipping 22 matching lines @@
 #include "base/time.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_export.h"
 #include "media/base/pipeline_status.h"
 #include "media/base/video_frame.h"
 
 struct AVStream;
 
 namespace media {
 
+class AudioDecoderConfig;
 class Buffer;
 class Decoder;
 class DemuxerStream;
 class Filter;
 class FilterHost;
 
 struct PipelineStatistics;
 
 // Used to specify video preload states. They are "hints" to the browser about
 // how aggressively the browser should load and buffer data.
@@ skipping 116 matching lines @@
     UNKNOWN,
     AUDIO,
     VIDEO,
     NUM_TYPES,  // Always keep this entry as the last one!
   };
 
   // Schedules a read.  When the |read_callback| is called, the downstream
   // filter takes ownership of the buffer by AddRef()'ing the buffer.
   virtual void Read(const ReadCallback& read_callback) = 0;
 
   // Returns an |AVStream*| if supported, or NULL.

[Ami GONE FROM CHROMIUM, 2011/09/12 20:54:21]

Is there a chance to remove this at the same time?

[scherkus (not reviewing), 2011/09/19 21:19:45]

Not yet :\

[Ami GONE FROM CHROMIUM, 2011/09/29 18:16:35]

How about now that AdaptiveDemuxer is dead? :)

   virtual AVStream* GetAVStream();
 
+  // Returns a weak reference to the audio decoder configuration if present,

[Ami GONE FROM CHROMIUM, 2011/09/12 20:54:21]

"weak reference"??

+  // NULL otherwise.
+  virtual AudioDecoderConfig* audio_decoder_config() = 0;
+
   // Returns the type of stream.
   virtual Type type() = 0;
 
   virtual void EnableBitstreamConverter() = 0;
 
  protected:
   friend class base::RefCountedThreadSafe<DemuxerStream>;
   virtual ~DemuxerStream();
 };
 
@@ skipping 120 matching lines @@
   // buffer.
   virtual bool HasEnded() = 0;
 
   // Sets the output volume.
   virtual void SetVolume(float volume) = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_FILTERS_H_