Support (E)AC3 passthrough

content/browser/renderer_host/media/audio_sync_reader.cc

 // 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.
 
 #include "content/browser/renderer_host/media/audio_sync_reader.h"
 
 #include <algorithm>
 #include <limits>
 #include <string>
 #include <utility>
@@ skipping 56 matching lines @@
       maximum_wait_time_(base::TimeDelta::FromMilliseconds(20)),
 #endif
       buffer_index_(0) {
   DCHECK_EQ(static_cast<size_t>(packet_size_),
             sizeof(media::AudioOutputBufferParameters) +
                 AudioBus::CalculateMemorySize(params));
   AudioOutputBuffer* buffer =
       reinterpret_cast<AudioOutputBuffer*>(shared_memory_->memory());
   output_bus_ = AudioBus::WrapMemory(params, buffer->audio);
   output_bus_->Zero();
+  output_bus_->set_is_bitstream_format(params.IsBitstreamFormat());
 }
 
 AudioSyncReader::~AudioSyncReader() {
   if (!renderer_callback_count_)
     return;
 
   DVLOG(1) << "Trailing glitch count on destruction: "
            << trailing_renderer_missed_callback_count_;
 
   // Subtract 'trailing' count of callbacks missed just before the destructor
@@ skipping 116 matching lines @@
                    << renderer_missed_callback_count_;
       if (renderer_missed_callback_count_ == 100)
         LOG(WARNING) << "(log cap reached, suppressing further logs)";
     }
     dest->Zero();
     return;
   }
 
   trailing_renderer_missed_callback_count_ = 0;
 
   if (mute_audio_)

[DaleCurtis, 2017/06/15 21:46:31]

Just return instead of having else block.

[AndyWu, 2017/08/02 01:43:38]

Done.

     dest->Zero();
-  else
+  else {
+    if (output_bus_->is_bitstream_format()) {
+      AudioOutputBuffer* buffer =
+          reinterpret_cast<AudioOutputBuffer*>(shared_memory_->memory());
+      output_bus_->set_frames(buffer->params.frames);
+      output_bus_->set_data_size(buffer->params.data_size);
+    }
     output_bus_->CopyTo(dest);
+  }
 }
 
 void AudioSyncReader::Close() {
   socket_->Close();
 }
 
 bool AudioSyncReader::WaitUntilDataIsReady() {
   TRACE_EVENT0("audio", "AudioSyncReader::WaitUntilDataIsReady");
   base::TimeDelta timeout = maximum_wait_time_;
   const base::TimeTicks start_time = base::TimeTicks::Now();
@@ skipping 41 matching lines @@
                                base::TimeDelta::FromMilliseconds(1),
                                base::TimeDelta::FromMilliseconds(1000),
                                50);
     return false;
   }
 
   return true;
 }
 
 }  // namespace content