Fire CanPlayThrough immediately for local and streaming media files

media/filters/dummy_demuxer.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.
 
 // Implements the Demuxer interface. DummyDemuxer returns corresponding
 // DummyDemuxerStream as signal for media pipeline to construct correct
-// playback channels.
+// playback channels. Used in WebRTC local video capture pipeline, where
+// demuxing is not needed.
 
 #ifndef MEDIA_FILTERS_DUMMY_DEMUXER_H_
 #define MEDIA_FILTERS_DUMMY_DEMUXER_H_
 
 #include <vector>
 
 #include "media/base/audio_decoder_config.h"
 #include "media/base/demuxer.h"
 #include "media/base/video_decoder_config.h"
 
@@ skipping 15 matching lines @@
 
   Type type_;
   AudioDecoderConfig audio_config_;
   VideoDecoderConfig video_config_;
 
   DISALLOW_COPY_AND_ASSIGN(DummyDemuxerStream);
 };
 
 class DummyDemuxer : public Demuxer {
  public:
-  DummyDemuxer(bool has_video, bool has_audio);
+  DummyDemuxer(bool has_video, bool has_audio, bool local_source);
   virtual ~DummyDemuxer();
 
   // Demuxer implementation.
   virtual scoped_refptr<DemuxerStream> GetStream(
       DemuxerStream::Type type) OVERRIDE;
   virtual void SetPreload(Preload preload) OVERRIDE;
   virtual base::TimeDelta GetStartTime() const OVERRIDE;
   virtual int GetBitrate() OVERRIDE;
+  virtual bool IsLocalSource() OVERRIDE;
 
  private:
   bool has_video_;
   bool has_audio_;
+  bool local_source_;
   std::vector< scoped_refptr<DummyDemuxerStream> > streams_;
 
   DISALLOW_COPY_AND_ASSIGN(DummyDemuxer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_DUMMY_DEMUXER_H_