Fix potential threading issues in NetworkChangeNotifierAndroid.

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 base {
+
+class TaskRunner;
+
+}  // namespace base
+
 namespace net {
 
 class NetworkChangeNotifier;
 
 // NetworkChangeNotifierFactory creates Android-specific specialization of
 // NetworkChangeNotifier.
 class NetworkChangeNotifierFactoryAndroid :
     public NetworkChangeNotifierFactory {
  public:
-  NetworkChangeNotifierFactoryAndroid();
+  NetworkChangeNotifierFactoryAndroid(base::TaskRunner* ui_task_runner);
   virtual ~NetworkChangeNotifierFactoryAndroid();
 
   // Overrides of NetworkChangeNotifierFactory.
   virtual NetworkChangeNotifier* CreateInstance() OVERRIDE;
+
+ private:
+  base::TaskRunner* const ui_task_runner_;
 };
 
 }  // namespace net
 
 #endif  // NET_ANDROID_NETWORK_CHANGE_NOTIFIER_FACTORY_H_