Cheaper thread-safe atomic initialization of static references.

Source/core/page/NetworkStateNotifier.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 21 matching lines @@
 #include "wtf/Assertions.h"
 #include "wtf/Functional.h"
 #include "wtf/MainThread.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/Threading.h"
 
 namespace blink {
 
 NetworkStateNotifier& networkStateNotifier()
 {
-    AtomicallyInitializedStatic(NetworkStateNotifier*, networkStateNotifier = new NetworkStateNotifier);
-    return *networkStateNotifier;
+    AtomicallyInitializedStaticReference(NetworkStateNotifier, networkStateNotifier, new NetworkStateNotifier);
+    return networkStateNotifier;
 }
 
 void NetworkStateNotifier::setOnLine(bool onLine)
 {
     ASSERT(isMainThread());
 
     {
         MutexLocker locker(m_mutex);
         if (m_isOnLine == onLine)
             return;
@@ skipping 118 matching lines @@
 
     list->zeroedObservers.clear();
 
     if (list->observers.isEmpty()) {
         MutexLocker locker(m_mutex);
         m_observers.remove(context); // deletes list
     }
 }
 
 } // namespace blink