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

ui/app_list/views/apps_container_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_APPS_CONTAINER_VIEW_H_
 #define UI_APP_LIST_VIEWS_APPS_CONTAINER_VIEW_H_
 
 #include <vector>
 
 #include "ui/app_list/app_list_folder_item.h"
@@ skipping 46 matching lines @@
       ApplicationDragAndDropHost* drag_and_drop_host);
 
   // Transits the UI from folder view to root lelve apps grid view when
   // re-parenting a child item of |folder_item|.
   void ReparentFolderItemTransit(AppListFolderItem* folder_item);
 
   // Returns true if it is currently showing an active folder page.
   bool IsInFolderView() const;
 
   // views::View overrides:
-  virtual gfx::Size GetPreferredSize() OVERRIDE;
+  virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual void Layout() OVERRIDE;
   virtual bool OnKeyPressed(const ui::KeyEvent& event) OVERRIDE;
 
   // TopIconAnimationObserver overrides:
   virtual void OnTopIconAnimationsComplete() OVERRIDE;
 
   AppsGridView* apps_grid_view() { return apps_grid_view_; }
   FolderBackgroundView* folder_background_view() {
      return folder_background_view_;
   }
@@ skipping 34 matching lines @@
 
   size_t top_icon_animation_pending_count_;
 
   DISALLOW_COPY_AND_ASSIGN(AppsContainerView);
 };
 
 }  // namespace app_list
 
 
 #endif  // UI_APP_LIST_VIEWS_APPS_CONTAINER_VIEW_H_