views: Make view::Views::GetPreferredSize() const.

ui/views/window/custom_frame_view.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 UI_VIEWS_WINDOW_CUSTOM_FRAME_VIEW_H_
 #define UI_VIEWS_WINDOW_CUSTOM_FRAME_VIEW_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 33 matching lines @@
   virtual int NonClientHitTest(const gfx::Point& point) OVERRIDE;
   virtual void GetWindowMask(const gfx::Size& size,
                              gfx::Path* window_mask) OVERRIDE;
   virtual void ResetWindowControls() OVERRIDE;
   virtual void UpdateWindowIcon() OVERRIDE;
   virtual void UpdateWindowTitle() OVERRIDE;
 
   // Overridden from View:
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
   virtual void Layout() OVERRIDE;
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
-  virtual gfx::Size GetMinimumSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
+  virtual gfx::Size GetMinimumSize() const OVERRIDE;
   virtual gfx::Size GetMaximumSize() OVERRIDE;
 
   // Overridden from ButtonListener:
   virtual void ButtonPressed(Button* sender, const ui::Event& event) OVERRIDE;
 
  private:
   // Returns the thickness of the border that makes up the window frame edges.
   // This does not include any client edge.
   int FrameBorderThickness() const;
 
@@ skipping 73 matching lines @@
 
   // Background painter for the window frame.
   scoped_ptr<FrameBackground> frame_background_;
 
   DISALLOW_COPY_AND_ASSIGN(CustomFrameView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WINDOW_CUSTOM_FRAME_VIEW_H_