Add support for midstream audio configuration changes.

media/base/demuxer_stream.h

 // Copyright (c) 2012 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_DEMUXER_STREAM_H_
 #define MEDIA_BASE_DEMUXER_STREAM_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/media_export.h"
@@ skipping 50 matching lines @@
 
   // Returns the video decoder configuration. It is an error to call this method
   // if type() != VIDEO.
   virtual VideoDecoderConfig video_decoder_config() = 0;
 
   // Returns the type of stream.
   virtual Type type() = 0;
 
   virtual void EnableBitstreamConverter() = 0;
 
+  // Whether or not this DemuxerStream allows midstream configuration changes.
+  virtual bool SupportsConfigChanges();
+
  protected:
   // Only allow concrete implementations to get deleted.
   virtual ~DemuxerStream();
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_DEMUXER_STREAM_H_