Part 1: Plumb render view ID to render host

media/audio/audio_output_device.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 "media/audio/audio_output_device.h"
 
 #include "base/debug/trace_event.h"
 #include "base/message_loop.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time.h"
@@ skipping 26 matching lines @@
 
 AudioOutputDevice::AudioOutputDevice(
     AudioOutputIPC* ipc,
     const scoped_refptr<base::MessageLoopProxy>& io_loop)
     : ScopedLoopObserver(io_loop),
       callback_(NULL),
       ipc_(ipc),
       stream_id_(0),
       play_on_start_(true),
       is_started_(false) {
-  CHECK(ipc_);
+  CHECK(ipc_.get());
 }
 
 void AudioOutputDevice::Initialize(const AudioParameters& params,
                              RenderCallback* callback) {
   CHECK_EQ(0, stream_id_) <<
       "AudioOutputDevice::Initialize() must be called before Start()";
 
   CHECK(!callback_);  // Calling Initialize() twice?
 
   audio_parameters_ = params;
@@ skipping 157 matching lines @@
       "AudioOutputDevice");
 
   // We handle the case where Play() and/or Pause() may have been called
   // multiple times before OnStreamCreated() gets called.
   is_started_ = true;
   if (play_on_start_)
     PlayOnIOThread();
 }
 
 void AudioOutputDevice::OnIPCClosed() {
-  ipc_ = NULL;
+  ipc_.reset();
 }
 
 void AudioOutputDevice::WillDestroyCurrentMessageLoop() {
   LOG(ERROR) << "IO loop going away before the audio device has been stopped";
   ShutDownOnIOThread();
 }
 
 // AudioOutputDevice::AudioThreadCallback
 
 AudioOutputDevice::AudioThreadCallback::AudioThreadCallback(
@@ skipping 35 matching lines @@
   // conversions that happen in the <audio> and WebRTC scenarios.
   InterleaveFloatToInt(audio_data_, shared_memory_.memory(),
       num_frames, audio_parameters_.bits_per_sample() / 8);
 
   // Let the host know we are done.
   SetActualDataSizeInBytes(&shared_memory_, memory_length_,
       num_frames * audio_parameters_.GetBytesPerFrame());
 }
 
 }  // namespace media.