Move views::Accelerator to ui in order to use it from aura code.

views/controls/combobox/native_combobox_views.h

 // Copyright (c) 2011 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 VIEWS_CONTROLS_COMBOBOX_NATIVE_COMBOBOX_VIEWS_H_
 #define VIEWS_CONTROLS_COMBOBOX_NATIVE_COMBOBOX_VIEWS_H_
 #pragma once
 
 #include "views/controls/combobox/native_combobox_wrapper.h"
 #include "views/controls/menu/menu_delegate.h"
@@ skipping 40 matching lines @@
   virtual bool HandleKeyPressed(const views::KeyEvent& event) OVERRIDE;
   virtual bool HandleKeyReleased(const views::KeyEvent& event) OVERRIDE;
   virtual void HandleFocus() OVERRIDE;
   virtual void HandleBlur() OVERRIDE;
   virtual gfx::NativeView GetTestingHandle() const OVERRIDE;
 
   // MenuDelegate overrides:
   virtual bool IsItemChecked(int id) const OVERRIDE;
   virtual bool IsCommandEnabled(int id) const OVERRIDE;
   virtual void ExecuteCommand(int id) OVERRIDE;
-  virtual bool GetAccelerator(int id, views::Accelerator* accelerator) OVERRIDE;
+  virtual bool GetAccelerator(int id, ui::Accelerator* accelerator) OVERRIDE;
 
   // class name of internal
   static const char kViewClassName[];
 
  private:
   // Returns the Combobox's font.
   const gfx::Font& GetFont() const;
 
   // Draw an arrow
   void DrawArrow(gfx::Canvas* canvas,
@@ skipping 23 matching lines @@
   // The maximum dimensions of the content in the dropdown
   int content_width_;
   int content_height_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeComboboxViews);
 };
 
 }  // namespace views
 
 #endif  // VIEWS_CONTROLS_COMBOBOX_NATIVE_COMBOBOX_VIEWS_H_