Add a mojo implementation of AudioOutputIPC.

content/renderer/pepper/pepper_platform_audio_output.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/renderer/pepper/pepper_platform_audio_output.h"
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "content/child/child_process.h"
 #include "content/common/media/audio_messages.h"
+#include "content/public/common/content_features.h"
+#include "content/renderer/media/audio_ipc_factory.h"
 #include "content/renderer/media/audio_message_filter.h"
 #include "content/renderer/pepper/audio_helper.h"
 #include "content/renderer/render_thread_impl.h"
 #include "ppapi/shared_impl/ppb_audio_config_shared.h"
 
 namespace content {
 
 // static
 PepperPlatformAudioOutput* PepperPlatformAudioOutput::Create(
     int sample_rate,
@@ skipping 103 matching lines @@
       io_task_runner_(ChildProcess::current()->io_task_runner()) {
 }
 
 bool PepperPlatformAudioOutput::Initialize(int sample_rate,
                                            int frames_per_buffer,
                                            int source_render_frame_id,
                                            AudioHelper* client) {
   DCHECK(client);
   client_ = client;
 
-  RenderThreadImpl* const render_thread = RenderThreadImpl::current();
-  ipc_ = render_thread->audio_message_filter()->CreateAudioOutputIPC(
-      source_render_frame_id);
+  if (base::FeatureList::IsEnabled(
+          features::kUseMojoAudioOutputStreamFactory)) {

[o1ka, 2017/04/20 10:36:00]

Instead of doing it here and in AOD separately, can we hide it inside
AudioIPCFactory?

[Max Morin, 2017/05/05 13:10:59]

I changed this, PTAL.

+    ipc_ = AudioIPCFactory::get()->CreateAudioOutputIPC(source_render_frame_id);
+  } else {
+    RenderThreadImpl* const render_thread = RenderThreadImpl::current();
+    ipc_ = render_thread->audio_message_filter()->CreateAudioOutputIPC(
+        source_render_frame_id);
+  }
   CHECK(ipc_);
 
   media::AudioParameters params(media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
                                 media::CHANNEL_LAYOUT_STEREO,
                                 sample_rate,
                                 ppapi::kBitsPerAudioOutputSample,
                                 frames_per_buffer);
 
   io_task_runner_->PostTask(
       FROM_HERE, base::Bind(&PepperPlatformAudioOutput::InitializeOnIOThread,
@@ skipping 34 matching lines @@
     return;
 
   ipc_->CloseStream();
   ipc_.reset();
 
   Release();  // Release for the delegate, balances out the reference taken in
               // PepperPlatformAudioOutput::Create.
 }
 
 }  // namespace content