Virtual destructors should have virtual keyword.

chrome/browser/ui/gtk/reload_button_gtk.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_UI_GTK_RELOAD_BUTTON_GTK_H_
 #define CHROME_BROWSER_UI_GTK_RELOAD_BUTTON_GTK_H_
 #pragma once
 
 #include <gtk/gtk.h>
 
 #include "base/basictypes.h"
 #include "base/timer.h"
 #include "chrome/browser/ui/gtk/custom_button.h"
 #include "chrome/browser/ui/gtk/owned_widget_gtk.h"
 #include "content/common/notification_observer.h"
 #include "content/common/notification_registrar.h"
 #include "ui/base/gtk/gtk_signal.h"
 
 class Browser;
 class GtkThemeService;
 class LocationBarViewGtk;
 class Task;
 
 class ReloadButtonGtk : public NotificationObserver {
  public:
   enum Mode { MODE_RELOAD = 0, MODE_STOP };
 
   ReloadButtonGtk(LocationBarViewGtk* location_bar, Browser* browser);
-  ~ReloadButtonGtk();
+  virtual ~ReloadButtonGtk();
 
   GtkWidget* widget() const { return widget_.get(); }
 
   // Ask for a specified button state.  If |force| is true this will be applied
   // immediately.
   void ChangeMode(Mode mode, bool force);
 
   // Provide NotificationObserver implementation.
   virtual void Observe(NotificationType type,
                        const NotificationSource& source,
@@ skipping 54 matching lines @@
   // True if we should pretend the button is hovered.
   bool testing_mouse_hovered_;
   // Increments when we would tell the browser to "reload", so
   // test code can tell whether we did so (as there may be no |browser_|).
   int testing_reload_count_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(ReloadButtonGtk);
 };
 
 #endif  // CHROME_BROWSER_UI_GTK_RELOAD_BUTTON_GTK_H_