Fix race condition in NetworkChangeNotifier on Android.

net/android/network_change_notifier_factory_android.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 NET_ANDROID_NETWORK_CHANGE_NOTIFIER_FACTORY_ANDROID_H_
 #define NET_ANDROID_NETWORK_CHANGE_NOTIFIER_FACTORY_ANDROID_H_
 
 #include "base/compiler_specific.h"
 #include "net/base/network_change_notifier_factory.h"
 
 namespace net {
 
 class NetworkChangeNotifier;
 
 // NetworkChangeNotifierFactory creates Android-specific specialization of
 // NetworkChangeNotifier.
 class NetworkChangeNotifierFactoryAndroid :
     public NetworkChangeNotifierFactory {
  public:
   NetworkChangeNotifierFactoryAndroid();
+  virtual ~NetworkChangeNotifierFactoryAndroid();
 
   // Overrides of NetworkChangeNotifierFactory.
   virtual NetworkChangeNotifier* CreateInstance() OVERRIDE;
 };
 
 }  // namespace net
 
 #endif  // NET_ANDROID_NETWORK_CHANGE_NOTIFIER_FACTORY_H_