Support (E)AC3 passthrough

media/base/audio_renderer_mixer.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_AUDIO_RENDERER_MIXER_H_
 #define MEDIA_BASE_AUDIO_RENDERER_MIXER_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 68 matching lines @@
   // Output sink for this mixer.
   const scoped_refptr<AudioRendererSink> audio_sink_;
 
   // ---------------[ All variables below protected by |lock_| ]---------------
   base::Lock lock_;
 
   // List of error callbacks used by this mixer.
   typedef std::list<base::Closure> ErrorCallbackList;
   ErrorCallbackList error_callbacks_;
 
+  AudioConverter::InputCallback* raw_input_;
+
   // Each of these converters mixes inputs with a given sample rate and
   // resamples them to the output sample rate. Inputs not reqiuring resampling
   // go directly to |master_converter_|.
   AudioConvertersMap converters_;
 
   // Master converter which mixes all the outputs from |converters_| as well as
   // mixer inputs that are in the output sample rate.
   AudioConverter master_converter_;
 
   // Handles physical stream pause when no inputs are playing.  For latency
   // reasons we don't want to immediately pause the physical stream.
   base::TimeDelta pause_delay_;
   base::TimeTicks last_play_time_;
   bool playing_;
 
   // Tracks the maximum number of simultaneous mixer inputs and logs it into
   // UMA histogram upon the destruction.
   std::unique_ptr<UMAMaxValueTracker> input_count_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererMixer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_RENDERER_MIXER_H_