ash: Cleanup class/struct forward declarations

ash/common/frame/caption_buttons/frame_size_button_delegate.h

 // Copyright 2014 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_COMMON_FRAME_CAPTION_BUTTONS_FRAME_SIZE_BUTTON_DELEGATE_H_
 #define ASH_COMMON_FRAME_CAPTION_BUTTONS_FRAME_SIZE_BUTTON_DELEGATE_H_
 
 #include "ash/ash_export.h"
 #include "ash/common/frame/caption_buttons/caption_button_types.h"
 
 namespace gfx {
-class Insets;
 class Point;
-class Vector2d;
 }
 
 namespace ash {
 class FrameCaptionButton;
 
 // Delegate interface for FrameSizeButton.
 class ASH_EXPORT FrameSizeButtonDelegate {
  public:
   enum Animate { ANIMATE_YES, ANIMATE_NO };
 
@@ skipping 21 matching lines @@
       const FrameCaptionButton* to_hover,
       const FrameCaptionButton* to_press) = 0;
 
  protected:
   virtual ~FrameSizeButtonDelegate() {}
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_FRAME_CAPTION_BUTTONS_FRAME_SIZE_BUTTON_DELEGATE_H_