Mojo interfaces needed for switching audio rendering stream creation and closing from IPC to Mojo

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index 08b8b0b3756fc55302e80b7f8df2d3f071f2123a..8ddf597597f6863bdf06d8b97b07bbb5a86c1549 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -29,6 +29,7 @@
 #include "content/common/storage_partition_service.mojom.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/renderer/gpu/compositor_dependencies.h"
+#include "content/renderer/media/audio_output_client.h"
 #include "gpu/ipc/client/gpu_channel_host.h"
 #include "net/base/network_change_notifier.h"
 #include "third_party/WebKit/public/platform/WebConnectionType.h"
@@ -564,6 +565,8 @@ class CONTENT_EXPORT RenderThreadImpl
   // Used on the render thread.
   std::unique_ptr<VideoCaptureImplManager> vc_manager_;
 
+  AudioOutputClient* audio_output_client_;
+
   // Used for communicating registering AEC dump consumers with the browser and
   // receving AEC dump file handles when AEC dump is enabled. An AEC dump is
   // diagnostic audio data for WebRTC stored locally when enabled by the user in