Offline state detection for linux, using new D-Bus library.

net/base/network_change_notifier.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 NET_BASE_NETWORK_CHANGE_NOTIFIER_H_
 #define NET_BASE_NETWORK_CHANGE_NOTIFIER_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/observer_list_threadsafe.h"
@@ skipping 118 matching lines @@
   NetworkChangeNotifier();
 
   // Broadcasts a notification to all registered observers.  Note that this
   // happens asynchronously, even for observers on the current thread, even in
   // tests.
   static void NotifyObserversOfIPAddressChange();
   static void NotifyObserversOfOnlineStateChange();
   static void NotifyObserversOfDNSChange();
 
  private:
+  friend class NetworkChangeNotifierLinuxTest;
   friend class NetworkChangeNotifierWinTest;
 
   // Allows a second NetworkChangeNotifier to be created for unit testing, so
   // the test suite can create a MockNetworkChangeNotifier, but platform
   // specific NetworkChangeNotifiers can also be created for testing.  To use,
   // create an DisableForTest object, and then create the new
   // NetworkChangeNotifier object.  The NetworkChangeNotifier must be
   // destroyed before the DisableForTest object, as its destruction will restore
   // the original NetworkChangeNotifier.
   class NET_EXPORT_PRIVATE DisableForTest {
@@ skipping 12 matching lines @@
       online_state_observer_list_;
   const scoped_refptr<ObserverListThreadSafe<DNSObserver> >
       resolver_state_observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkChangeNotifier);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_NETWORK_CHANGE_NOTIFIER_H_