mash: Move shelf menu code to //ash/common/shelf

ash/shelf/shelf_alignment_menu.h

-// Copyright 2013 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_SHELF_SHELF_ALIGNMENT_MENU_H_
-#define ASH_SHELF_SHELF_ALIGNMENT_MENU_H_
-
-#include "ash/ash_export.h"
-#include "base/macros.h"
-#include "ui/base/models/simple_menu_model.h"
-
-namespace ash {
-
-class WmShelf;
-
-// Submenu for choosing the alignment of the shelf.
-class ASH_EXPORT ShelfAlignmentMenu : public ui::SimpleMenuModel,
-                                      public ui::SimpleMenuModel::Delegate {
- public:
-  explicit ShelfAlignmentMenu(WmShelf* wm_shelf);
-  ~ShelfAlignmentMenu() override;
-
-  // ui::SimpleMenuModel::Delegate overrides:
-  bool IsCommandIdChecked(int command_id) const override;
-  bool IsCommandIdEnabled(int command_id) const override;
-  bool GetAcceleratorForCommandId(int command_id,
-                                  ui::Accelerator* accelerator) override;
-  void ExecuteCommand(int command_id, int event_flags) override;
-
- private:
-  enum MenuItem {
-    // Offset so as not to interfere with other menus.
-    MENU_ALIGN_LEFT = 500,
-    MENU_ALIGN_RIGHT,
-    MENU_ALIGN_BOTTOM,
-  };
-
-  WmShelf* wm_shelf_;
-
-  DISALLOW_COPY_AND_ASSIGN(ShelfAlignmentMenu);
-};
-
-}  // namespace ash
-
-#endif  // ASH_SHELF_SHELF_ALIGNMENT_MENU_H_