Remove calls to MessageLoop::current() in components.

components/mus/gpu/gpu_service_mus.h

Index: components/mus/gpu/gpu_service_mus.h
diff --git a/components/mus/gpu/gpu_service_mus.h b/components/mus/gpu/gpu_service_mus.h
index a371bdf4da50fa9f8236cb8e4202f290529a9275..b6bfd1b69f59036f845de51d5b5968cd72e7c164 100644
--- a/components/mus/gpu/gpu_service_mus.h
+++ b/components/mus/gpu/gpu_service_mus.h
@@ -134,8 +134,8 @@ class GpuServiceMus : public gpu::GpuChannelManagerDelegate,
   // The next client id.
   int next_client_id_;
 
-  // The main thread message loop.
-  base::MessageLoop* main_message_loop_;
+  // The main thread task runner.
+  scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
 
   // An event that will be signalled when we shutdown.
   base::WaitableEvent shutdown_event_;