Virtual destructors should have virtual keyword.

chrome/browser/extensions/extension_browser_event_router.h

 // Copyright (c) 2011 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 CHROME_BROWSER_EXTENSIONS_EXTENSION_BROWSER_EVENT_ROUTER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_BROWSER_EVENT_ROUTER_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 18 matching lines @@
 class ExtensionBrowserEventRouter : public TabStripModelObserver,
 #if defined(TOOLKIT_VIEWS)
                                     public views::WidgetFocusChangeListener,
 #elif defined(TOOLKIT_GTK)
                                     public ui::ActiveWindowWatcherX::Observer,
 #endif
                                     public BrowserList::Observer,
                                     public NotificationObserver {
  public:
   explicit ExtensionBrowserEventRouter(Profile* profile);
-  ~ExtensionBrowserEventRouter();
+  virtual ~ExtensionBrowserEventRouter();
 
   // Must be called once. Subsequent calls have no effect.
   void Init();
 
   // BrowserList::Observer
   virtual void OnBrowserAdded(const Browser* browser);
   virtual void OnBrowserRemoved(const Browser* browser);
   virtual void OnBrowserSetLastActive(const Browser* browser);
 
 #if defined(TOOLKIT_VIEWS)
@@ skipping 129 matching lines @@
   int focused_window_id_;
 
   // The main profile (non-OTR) profile which will be used to send events not
   // associated with any browser.
   Profile* profile_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionBrowserEventRouter);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_BROWSER_EVENT_ROUTER_H_