Cleanup: Remove unneeded forward declarations from chrome/browser/ui/views.

chrome/browser/ui/views/frame/browser_non_client_frame_view_aura.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 CHROME_BROWSER_UI_VIEWS_FRAME_BROWSER_NON_CLIENT_FRAME_VIEW_AURA_H_
 #define CHROME_BROWSER_UI_VIEWS_FRAME_BROWSER_NON_CLIENT_FRAME_VIEW_AURA_H_
 #pragma once
 
 #include "ui/aura_shell/window_frame.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/ui/views/frame/browser_non_client_frame_view.h"
 #include "views/controls/button/button.h"
 #include "views/widget/widget.h"
 
 class BrowserFrame;
 class BrowserView;
 class FrameBackground;
 class WindowControlButton;
 
-namespace gfx {
-class canvas;
-}
-namespace views {
-class CustomButton;
-}
-
 class BrowserNonClientFrameViewAura : public BrowserNonClientFrameView,
                                       public views::ButtonListener,
                                       public views::Widget::Observer,
                                       public aura_shell::WindowFrame {
  public:
   BrowserNonClientFrameViewAura(BrowserFrame* frame, BrowserView* browser_view);
   virtual ~BrowserNonClientFrameViewAura();
 
   // Control the slide-in animation of the frame background.
   void ShowFrameBackground();
@@ skipping 53 matching lines @@
 
   int last_hittest_code_;
   WindowControlButton* maximize_button_;
   WindowControlButton* close_button_;
   FrameBackground* frame_background_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserNonClientFrameViewAura);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_FRAME_BROWSER_NON_CLIENT_FRAME_VIEW_AURA_H_