Virtual destructors should have virtual keyword.

chrome/browser/history/history_notifications.h

 // Copyright (c) 2006-2008 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.
 
 // Structs that hold data used in broadcasting notifications.
 
 #ifndef CHROME_BROWSER_HISTORY_HISTORY_NOTIFICATIONS_H__
 #define CHROME_BROWSER_HISTORY_HISTORY_NOTIFICATIONS_H__
 #pragma once
 
@@ skipping 69 matching lines @@
 struct FaviconChangeDetails : public HistoryDetails {
   FaviconChangeDetails();
   virtual ~FaviconChangeDetails();
 
   std::set<GURL> urls;
 };
 
 // Details for HISTORY_KEYWORD_SEARCH_TERM_UPDATED.
 struct KeywordSearchTermDetails : public HistoryDetails {
   KeywordSearchTermDetails();
-  ~KeywordSearchTermDetails();
+  virtual ~KeywordSearchTermDetails();
 
   GURL url;
   TemplateURLID keyword_id;
   string16 term;
 };
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_HISTORY_NOTIFICATIONS_H__