[ash] Cleanup of ScopedOverviewAnimationSettings

ash/wm/overview/scoped_overview_animation_settings_factory.h

-// 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 ASH_WM_OVERVIEW_SCOPED_OVERVIEW_ANIMATION_SETTINGS_FACTORY_H_
-#define ASH_WM_OVERVIEW_SCOPED_OVERVIEW_ANIMATION_SETTINGS_FACTORY_H_
-
-#include <memory>
-
-#include "ash/wm/overview/overview_animation_type.h"
-
-namespace aura {
-class Window;
-}
-
-namespace ash {
-
-class ScopedOverviewAnimationSettings;
-
-// Factory for creating ScopedOverviewAnimationSettings.
-class ScopedOverviewAnimationSettingsFactory {
- public:
-  static ScopedOverviewAnimationSettingsFactory* Get();
-
-  virtual std::unique_ptr<ScopedOverviewAnimationSettings>
-  CreateOverviewAnimationSettings(OverviewAnimationType animation_type,
-                                  aura::Window* window) = 0;
-
- protected:
-  ScopedOverviewAnimationSettingsFactory();
-  virtual ~ScopedOverviewAnimationSettingsFactory();
-
- private:
-  static ScopedOverviewAnimationSettingsFactory* instance_;
-};
-
-}  // namespace ash
-
-#endif  // ASH_WM_OVERVIEW_SCOPED_OVERVIEW_ANIMATION_SETTINGS_FACTORY_H_