Add a histogram for video decoder fallback.

media/filters/decoder_stream.h

 // Copyright 2014 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_FILTERS_DECODER_STREAM_H_
 #define MEDIA_FILTERS_DECODER_STREAM_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
@@ skipping 101 matching lines @@
     STATE_UNINITIALIZED,
     STATE_INITIALIZING,
     STATE_NORMAL,  // Includes idle, pending decoder decode/reset.
     STATE_FLUSHING_DECODER,
     STATE_PENDING_DEMUXER_READ,
     STATE_REINITIALIZING_DECODER,
     STATE_END_OF_STREAM,  // End of stream reached; returns EOS on all reads.
     STATE_ERROR
   };
 
+  DemuxerStream::Type GetStreamType() {
+    return StreamType;
+  }
+
   void SelectDecoder(const SetDecryptorReadyCB& set_decryptor_ready_cb);
 
   // Called when |decoder_selector| selected the |selected_decoder|.
   // |decrypting_demuxer_stream| was also populated if a DecryptingDemuxerStream
   // is created to help decrypt the encrypted stream.
   void OnDecoderSelected(
       scoped_ptr<Decoder> selected_decoder,
       scoped_ptr<DecryptingDemuxerStream> decrypting_demuxer_stream);
 
   // Satisfy pending |read_cb_| with |status| and |output|.
@@ skipping 81 matching lines @@
 
 template <>
 int DecoderStream<DemuxerStream::AUDIO>::GetMaxDecodeRequests() const;
 
 typedef DecoderStream<DemuxerStream::VIDEO> VideoFrameStream;
 typedef DecoderStream<DemuxerStream::AUDIO> AudioBufferStream;
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_DECODER_STREAM_H_