Add undeclared virtual destructors part 2...

app/menus/button_menu_item_model.h

 // Copyright (c) 2010 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 APP_MENUS_BUTTON_MENU_ITEM_MODEL_H_
 #define APP_MENUS_BUTTON_MENU_ITEM_MODEL_H_
 
 #include <vector>
 
 #include "base/string16.h"
@@ skipping 12 matching lines @@
   };
 
   class Delegate {
    public:
     // Some command ids have labels that change over time.
     virtual bool IsLabelForCommandIdDynamic(int command_id) const;
     virtual string16 GetLabelForCommandId(int command_id) const;
 
     // Performs the action associated with the specified command id.
     virtual void ExecuteCommand(int command_id) = 0;
+
+   protected:
+    virtual ~Delegate() {}
   };
 
   ButtonMenuItemModel(int string_id, ButtonMenuItemModel::Delegate* delegate);
   ~ButtonMenuItemModel();
 
   // Adds a button that will emit |command_id|. All buttons created through
   // this method will have the same size, based on the largest button.
   void AddGroupItemWithStringId(int command_id, int string_id);
 
   // Adds a button that has an icon instead of a label.
@@ skipping 43 matching lines @@
   std::vector<Item> items_;
 
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(ButtonMenuItemModel);
 };
 
 }  // namespace menus
 
 #endif  // APP_MENUS_BUTTON_MENU_ITEM_MODEL_H_