mus::GpuService: Support establish GpuChannel asynchronously.

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 3fc1dfe73df87f6b55529d03272309c81182b151..a2f52d336b92b4dcab34f1210413521fde94de66 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -199,6 +199,7 @@
 #endif
 
 #if defined(MOJO_SHELL_CLIENT)
+#include "components/mus/common/gpu_service.h"
 #include "content/public/common/mojo_shell_connection.h"
 #include "content/renderer/mus/render_widget_mus_connection.h"
 #include "content/renderer/mus/render_widget_window_tree_client_factory.h"
@@ -1812,8 +1813,10 @@ RenderThreadImpl::CreateCompositorOutputSurface(
     use_software = true;
 
 #if defined(MOJO_SHELL_CLIENT)
-  if (MojoShellConnection::GetForProcess() && !use_software &&
+  auto shell_connection = MojoShellConnection::GetForProcess();
+  if (shell_connection && !use_software &&
       command_line.HasSwitch(switches::kUseMusInRenderer)) {
+    mus::GpuService::Initialize(shell_connection->GetConnector());
     RenderWidgetMusConnection* connection =
         RenderWidgetMusConnection::GetOrCreate(routing_id);
     return connection->CreateOutputSurface();