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

ui/app_list/views/app_list_folder_view.h

 // Copyright 2013 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_APP_LIST_VIEWS_APP_LIST_FOLDER_VIEW_H_
 #define UI_APP_LIST_VIEWS_APP_LIST_FOLDER_VIEW_H_
 
 #include <string>
 
 #include "ui/app_list/app_list_item_list_observer.h"
@@ skipping 44 matching lines @@
 
   void UpdateFolderNameVisibility(bool visible);
 
   // Hides the view immediately without animation.
   void HideViewImmediately();
 
   // Closes the folder page and goes back the top level page.
   void CloseFolderPage();
 
   // views::View
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual void Layout() OVERRIDE;
   virtual bool OnKeyPressed(const ui::KeyEvent& event) OVERRIDE;
 
   // AppListModelObserver
   virtual void OnAppListItemWillBeDeleted(AppListItem* item) OVERRIDE;
 
   // ui::ImplicitAnimationObserver
   virtual void OnImplicitAnimationsCompleted() OVERRIDE;
 
   AppsGridView* items_grid_view() { return items_grid_view_; }
@@ skipping 48 matching lines @@
   bool hide_for_reparent_;
 
   base::string16 accessible_name_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListFolderView);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_VIEWS_APP_LIST_FOLDER_VIEW_H_