services/ui: Use a gpu::GpuChannelHost when creating ui::OutputSurface.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index a6ba224890db29727486a1ada531d87055d337d8..7d1936939b594bc3bb700f2aa2db78ea7d836c90 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -1818,7 +1818,9 @@ RenderThreadImpl::CreateCompositorOutputSurface(
       command_line.HasSwitch(switches::kUseMusInRenderer)) {
     RenderWidgetMusConnection* connection =
         RenderWidgetMusConnection::GetOrCreate(routing_id);
-    return connection->CreateOutputSurface(gpu_service_.get());
+    scoped_refptr<gpu::GpuChannelHost> gpu_channel_host =
+        EstablishGpuChannelSync();
+    return connection->CreateOutputSurface(std::move(gpu_channel_host));
   }
 #endif