Add a mojo implementation of AudioOutputIPC.

content/renderer/pepper/pepper_platform_audio_output.cc

Index: content/renderer/pepper/pepper_platform_audio_output.cc
diff --git a/content/renderer/pepper/pepper_platform_audio_output.cc b/content/renderer/pepper/pepper_platform_audio_output.cc
index e847e72478061d57fdd996277bd766090285941a..db63c1ce864ba1701560591a77149e45ebcb094b 100644
--- a/content/renderer/pepper/pepper_platform_audio_output.cc
+++ b/content/renderer/pepper/pepper_platform_audio_output.cc
@@ -12,6 +12,8 @@
 #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"
@@ -135,9 +137,14 @@ bool PepperPlatformAudioOutput::Initialize(int sample_rate,
   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,