mustash: enable GPU Compositing in renderer

content/renderer/render_view_impl.cc

Index: content/renderer/render_view_impl.cc
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index 8bb66f17ae1b3486bd1dbb52df9164a85e8d85e4..879de79794c68ad77d8ab28140d8be63e0eeeffe 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -210,6 +210,11 @@
 #include "content/renderer/media/webrtc/peer_connection_dependency_factory.h"
 #endif
 
+#if defined(MOJO_SHELL_CLIENT)
+#include "content/public/common/mojo_shell_connection.h"
+#include "content/renderer/render_widget_mus_connection.h"
+#endif
+
 using blink::WebAXObject;
 using blink::WebApplicationCacheHost;
 using blink::WebApplicationCacheHostClient;
@@ -1711,6 +1716,18 @@ void RenderViewImpl::AttachWebFrameWidget(blink::WebWidget* frame_widget) {
   frame_widget_ = frame_widget;
 }
 
+scoped_ptr<cc::OutputSurface> RenderViewImpl::CreateOutputSurface(
+    bool fallback) {
+#if defined(MOJO_SHELL_CLIENT)
+  if (MojoShellConnection::Get()->GetApplication() && !fallback) {
+    RenderWidgetMusConnection* connection =
+        RenderWidgetMusConnection::GetOrCreate(routing_id());
+    return connection->CreateOutputSurface();
+  }
+#endif
+  return RenderWidget::CreateOutputSurface(fallback);
+}
+
 void RenderViewImpl::SetZoomLevel(double zoom_level) {
   webview()->setZoomLevel(zoom_level);
   FOR_EACH_OBSERVER(RenderViewObserver, observers_, OnZoomLevelChanged());