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

ui/views/controls/tabbed_pane/tabbed_pane.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_TABBED_PANE_TABBED_PANE_H_
 #define UI_VIEWS_CONTROLS_TABBED_PANE_TABBED_PANE_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/strings/string16.h"
@@ skipping 36 matching lines @@
   // is currently empty, the new tab is selected.
   void AddTabAtIndex(int index, const base::string16& title, View* contents);
 
   // Selects the tab at |index|, which must be valid.
   void SelectTabAt(int index);
 
   // Selects |tab| (the tabstrip view, not its content) if it is valid.
   void SelectTab(Tab* tab);
 
   // Overridden from View:
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual const char* GetClassName() const OVERRIDE;
 
  private:
    friend class TabStrip;
 
    // Get the Tab (the tabstrip view, not its content) at the valid |index|.
    Tab* GetTabAt(int index);
 
   // Overridden from View:
   virtual void Layout() OVERRIDE;
@@ skipping 13 matching lines @@
 
   // The selected tab index or -1 if invalid.
   int selected_tab_index_;
 
   DISALLOW_COPY_AND_ASSIGN(TabbedPane);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_TABBED_PANE_TABBED_PANE_H_