Revert of Rename MaximizeMode to TabletMode

ash/wm/tablet_mode/tablet_mode_backdrop_delegate_impl.h

-// Copyright 2017 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_TABLET_MODE_TABLET_MODE_BACKDROP_DELEGATE_IMPL_H_
-#define ASH_WM_TABLET_MODE_TABLET_MODE_BACKDROP_DELEGATE_IMPL_H_
-
-#include "ash/wm/workspace/backdrop_delegate.h"
-
-#include "ash/ash_export.h"
-#include "base/macros.h"
-
-namespace ash {
-
-// A backdrop delegate for MaximizedMode, which always creates a backdrop.
-// This is also used in the WorkspaceLayoutManagerBackdropTest, hence
-// is public.
-class ASH_EXPORT TabletModeBackdropDelegateImpl : public BackdropDelegate {
- public:
-  TabletModeBackdropDelegateImpl();
-  ~TabletModeBackdropDelegateImpl() override;
-
- protected:
-  bool HasBackdrop(aura::Window* window) override;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(TabletModeBackdropDelegateImpl);
-};
-
-}  // namespace ash
-
-#endif  // ASH_WM_TABLET_MODE_TABLET_MODE_BACKDROP_DELEGATE_IMPL_H_