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

ui/views/controls/throbber.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_CONTROLS_THROBBER_H_
 #define UI_VIEWS_CONTROLS_THROBBER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/time/time.h"
@@ skipping 19 matching lines @@
   virtual ~Throbber();
 
   // Start and stop the throbber animation
   virtual void Start();
   virtual void Stop();
 
   // Set custom throbber frames. Otherwise IDR_THROBBER is loaded.
   void SetFrames(const gfx::ImageSkia* frames);
 
   // Overridden from View:
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE;
 
  protected:
   // Specifies whether the throbber is currently animating or not
   bool running_;
 
  private:
   void Run();
 
   bool paint_while_stopped_;
@@ skipping 67 matching lines @@
 
   // The checkmark image.
   const gfx::ImageSkia* checkmark_;
 
   DISALLOW_COPY_AND_ASSIGN(CheckmarkThrobber);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_THROBBER_H_