Impl mus::mojom::GpuService to enable using Chrome IPC version gpu CmdBuf in mus

components/mus/public/cpp/lib/gpu_service.h

Index: components/mus/public/cpp/lib/gpu_service.h
diff --git a/components/mus/public/cpp/lib/gpu_service.h b/components/mus/public/cpp/lib/gpu_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..571a3537c14dd1c9be8b8ab2effff36afb8d5ae1
--- /dev/null
+++ b/components/mus/public/cpp/lib/gpu_service.h
@@ -0,0 +1,55 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENTS_MUS_PUBLIC_CPP_LIB_GPU_SERVICE_H_
+#define COMPONENTS_MUS_PUBLIC_CPP_LIB_GPU_SERVICE_H_
+
+#include <stdint.h>
+#include <vector>
+
+#include "base/macros.h"
+#include "base/synchronization/waitable_event.h"
+#include "base/threading/thread.h"
+#include "gpu/ipc/client/gpu_channel_host.h"
+
+namespace shell {
+class Connector;
+}
+
+namespace mus {
+
+class GpuMemoryBufferManagerMus;
+
+class GpuService : public gpu::GpuChannelHostFactory {
+ public:
+  scoped_refptr<gpu::GpuChannelHost> EstablishGpuChannel(
+      shell::Connector* connector);
+
+  static bool UseChromeGpuCommandBuffer();
+  static GpuService* GetInstance();
+
+ private:
+  friend struct base::DefaultSingletonTraits<GpuService>;
+
+  GpuService();
+  ~GpuService() override;
+
+  // gpu::GpuChannelHostFactory overrides:
+  bool IsMainThread() override;
+  scoped_refptr<base::SingleThreadTaskRunner> GetIOThreadTaskRunner() override;
+  std::unique_ptr<base::SharedMemory> AllocateSharedMemory(
+      size_t size) override;
+
+  base::MessageLoop* main_message_loop_;
+  base::WaitableEvent shutdown_event_;
+  base::Thread io_thread_;
+  std::unique_ptr<GpuMemoryBufferManagerMus> gpu_memory_buffer_manager_;
+  scoped_refptr<gpu::GpuChannelHost> gpu_channel_;
+
+  DISALLOW_COPY_AND_ASSIGN(GpuService);
+};
+
+}  // namespace mus
+
+#endif  // COMPONENTS_MUS_PUBLIC_CPP_LIB_GPU_SERVICE_CONNECTION_H_