Add support for config changes during playback to FFmpegVideoDecoder.

media/filters/source_buffer_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.
 
 // SourceBufferStream is a data structure that stores media Buffers in ranges.
 // Buffers can be appended out of presentation order. Buffers are retrieved by
 // seeking to the desired start point and calling GetNextBuffer(). Buffers are
 // returned in sequential presentation order.
 
 #ifndef MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_
@@ skipping 240 matching lines @@
   // True when the next call to Append() begins a new media segment.
   bool new_media_segment_;
 
   // The timestamp of the last buffer appended to the media segment, set to
   // kNoTimestamp() if the beginning of the segment.
   base::TimeDelta last_buffer_timestamp_;
 
   // Stores the largest distance between two adjacent buffers in this stream.
   base::TimeDelta max_interbuffer_distance_;
 
-// The maximum amount of data in bytes the stream will keep in memory.
+  // The maximum amount of data in bytes the stream will keep in memory.
   int memory_limit_;
 
+  // Indicates that a kConfigChanged status has been reported by GetNextBuffer()
+  // and the next GetCurrentXXXDecoderConfig() should update the current config.

[Ami GONE FROM CHROMIUM, 2012/08/17 15:16:59]

This comment implies that the contract is that GNB() will keep reporting kCC
until the client gets the new current config.  You might test for that if that's
really what you want the API to be.
But probably the API should be that a single kCC is fired and must be acted
upon, and then you can CHECK(!config_change_pending_) at the top of GNB().

[acolwell GONE FROM CHROMIUM, 2012/08/20 23:10:12]

That was the original intent, but I like your suggestion below.
Done.

+  bool config_change_pending_;
+
   DISALLOW_COPY_AND_ASSIGN(SourceBufferStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_