Give StatusTrayStateChangerProxy a virtual destructor.

chrome/browser/ui/views/status_icons/status_tray_win.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 CHROME_BROWSER_UI_VIEWS_STATUS_ICONS_STATUS_TRAY_WIN_H_
 #define CHROME_BROWSER_UI_VIEWS_STATUS_ICONS_STATUS_TRAY_WIN_H_
 
 #include <windows.h>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/status_icons/status_tray.h"
 
 class StatusIconWin;
 
 // A class that's responsible for increasing, if possible, the visibility
 // of a status tray icon on the taskbar. The default implementation sends
 // a task to a worker thread each time EnqueueChange is called.
 class StatusTrayStateChangerProxy {
  public:
+  virtual ~StatusTrayStateChangerProxy() {}
+
   // Called by StatusTrayWin to request upgraded visibility on the icon
   // represented by the |icon_id|, |window| pair.
   virtual void EnqueueChange(UINT icon_id, HWND window) = 0;
 };
 
 class StatusTrayWin : public StatusTray {
  public:
   StatusTrayWin();
   ~StatusTrayWin();
 
@@ skipping 40 matching lines @@
 
   // Manages changes performed on a background thread to manipulate visibility
   // of notification icons.
   scoped_ptr<StatusTrayStateChangerProxy> state_changer_proxy_;
 
   DISALLOW_COPY_AND_ASSIGN(StatusTrayWin);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_STATUS_ICONS_STATUS_TRAY_WIN_H_