views: Extract SystemMenuModel from native_menu_win.*.

chrome/browser/ui/views/frame/system_menu_model.h

+// Copyright (c) 2012 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 CHROME_BROWSER_UI_VIEWS_FRAME_SYSTEM_MENU_MODEL_H_
+#define CHROME_BROWSER_UI_VIEWS_FRAME_SYSTEM_MENU_MODEL_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "ui/base/models/simple_menu_model.h"
+
+// A SimpleMenuModel subclass that allows the system menu for a window to be
+// wrapped.
+class SystemMenuModel : public ui::SimpleMenuModel {
+ public:
+  explicit SystemMenuModel(ui::SimpleMenuModel::Delegate* delegate);
+  virtual ~SystemMenuModel();
+
+  // Overridden from ui::MenuModel:
+  virtual int GetFirstItemIndex(gfx::NativeMenu native_menu) const OVERRIDE;
+
+ protected:
+  // Overridden from ui::SimpleMenuModel:
+  virtual int FlipIndex(int index) const OVERRIDE;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(SystemMenuModel);
+};
+
+#endif  // CHROME_BROWSER_UI_VIEWS_FRAME_SYSTEM_MENU_MODEL_H_