Add support for config changes during playback to FFmpegVideoDecoder.

media/filters/source_buffer_stream.h

Index: media/filters/source_buffer_stream.h
diff --git a/media/filters/source_buffer_stream.h b/media/filters/source_buffer_stream.h
index e67a84d0a7a56f01f905d56ddb716029d718a33e..0e08327165c5f19d5109c455cdaf1d8c271bdd8a 100644
--- a/media/filters/source_buffer_stream.h
+++ b/media/filters/source_buffer_stream.h
@@ -258,9 +258,15 @@ class MEDIA_EXPORT SourceBufferStream {
   // 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 GetCurrentXXXDecoderConfig() must be called to update the current
+  // config. GetNextBuffer() must not be called again until
+  // GetCurrentXXXDecoderConfig() has been called.
+  bool config_change_pending_;
+
   DISALLOW_COPY_AND_ASSIGN(SourceBufferStream);
 };