app_list::SearchResult: Duplicate() is const.

ui/app_list/search_result.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_APP_LIST_SEARCH_RESULT_H_
 #define UI_APP_LIST_SEARCH_RESULT_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 109 matching lines @@
   // Returns the dimension at which this result's icon should be displayed.
   int GetPreferredIconDimension() const;
 
   void NotifyItemInstalled();
 
   void AddObserver(SearchResultObserver* observer);
   void RemoveObserver(SearchResultObserver* observer);
 
   // TODO(mukai): Remove this method and really simplify the ownership of
   // SearchResult. Ideally, SearchResult will be copyable.
-  virtual scoped_ptr<SearchResult> Duplicate() = 0;
+  virtual scoped_ptr<SearchResult> Duplicate() const = 0;
 
   // Opens the result.
   virtual void Open(int event_flags);
 
   // Invokes a custom action on the result. It does nothing by default.
   virtual void InvokeAction(int action_index, int event_flags);
 
   // Returns the context menu model for this item, or NULL if there is currently
   // no menu for the item (e.g. during install).
   // Note the returned menu model is owned by this item.
@@ skipping 27 matching lines @@
   int percent_downloaded_;
 
   ObserverList<SearchResultObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(SearchResult);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_SEARCH_RESULT_H_