Add virtual to ~TitleWatcher to appease clang.

chrome/test/ui_test_utils.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_TEST_UI_TEST_UTILS_H_
 #define CHROME_TEST_UI_TEST_UTILS_H_
 #pragma once
 
 #include <map>
 #include <queue>
@@ skipping 460 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(WindowedNotificationObserverWithDetails);
 };
 
 // Watches title changes on a tab, blocking until an expected title is set.
 class TitleWatcher : public NotificationObserver {
  public:
   // |tab_contents| must be non-NULL and needs to stay alive for the
   // entire lifetime of |this|. |expected_title| is the title that |this|
   // will wait for.
   TitleWatcher(TabContents* tab_contents, const string16& expected_title);
-  ~TitleWatcher();
+  virtual ~TitleWatcher();
 
   // Waits until the title for the tab is set to the |expected_title|
   // passed into the constructor.
   bool Wait() WARN_UNUSED_RESULT;
 
  private:
   // NotificationObserver
   virtual void Observe(NotificationType type,
                        const NotificationSource& source,
                        const NotificationDetails& details) OVERRIDE;
@@ skipping 87 matching lines @@
 
 // Takes a snapshot of the entire page, according to the width and height
 // properties of the DOM's document. Returns true on success. DOMAutomation
 // must be enabled.
 bool TakeEntirePageSnapshot(RenderViewHost* rvh,
                             SkBitmap* bitmap) WARN_UNUSED_RESULT;
 
 }  // namespace ui_test_utils
 
 #endif  // CHROME_TEST_UI_TEST_UTILS_H_