Add ShellDelegate, MediaDelegate and KeyboardUI stubs to mus ash

ash/gpu_support.h

-// Copyright 2014 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 ASH_GPU_SUPPORT_H_
-#define ASH_GPU_SUPPORT_H_
-
-#include <list>
-
-#include "ash/ash_export.h"
-#include "base/callback_forward.h"
-#include "base/process/process.h"
-
-namespace ash {
-
-// An interface to allow use of content::GpuDataManager to be injected in
-// configurations that permit a dependency on content.
-class ASH_EXPORT GPUSupport {
- public:
-  typedef base::Callback<void(const std::list<base::ProcessHandle>&)>
-      GetGpuProcessHandlesCallback;
-
-  virtual ~GPUSupport() {}
-
-  virtual bool IsPanelFittingDisabled() const = 0;
-
-  virtual void DisableGpuWatchdog() = 0;
-
-  virtual void GetGpuProcessHandles(
-      const GetGpuProcessHandlesCallback& callback) const = 0;
-};
-
-}  // namespace ash
-
-#endif  // ASH_GPU_SUPPORT_H_