Make DocumentLoader::timing return a reference

Source/core/frame/LocalDOMWindow.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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
@@ skipping 1547 matching lines @@
     } else if (eventType == EventTypeNames::beforeunload && allowsBeforeUnloadListeners(this)) {
         removeBeforeUnloadEventListener(this);
     }
 
     return true;
 }
 
 void LocalDOMWindow::dispatchLoadEvent()
 {
     RefPtrWillBeRawPtr<Event> loadEvent(Event::create(EventTypeNames::load));
-    if (frame() && frame()->loader().documentLoader() && !frame()->loader().documentLoader()->timing()->loadEventStart()) {
+    if (frame() && frame()->loader().documentLoader() && !frame()->loader().documentLoader()->timing().loadEventStart()) {
         // The DocumentLoader (and thus its DocumentLoadTiming) might get destroyed while dispatching
         // the event, so protect it to prevent writing the end time into freed memory.
         RefPtr<DocumentLoader> documentLoader = frame()->loader().documentLoader();
-        DocumentLoadTiming* timing = documentLoader->timing();
-        timing->markLoadEventStart();
+        DocumentLoadTiming& timing = documentLoader->timing();
+        timing.markLoadEventStart();
         dispatchEvent(loadEvent, document());
-        timing->markLoadEventEnd();
+        timing.markLoadEventEnd();
     } else
         dispatchEvent(loadEvent, document());
 
     // For load events, send a separate load event to the enclosing frame only.
     // This is a DOM extension and is independent of bubbling/capturing rules of
     // the DOM.
     FrameOwner* owner = frame() ? frame()->owner() : nullptr;
     if (owner)
         owner->dispatchLoad();
 
@@ skipping 257 matching lines @@
     return m_frameObserver->frame();
 }
 
 v8::Handle<v8::Object> LocalDOMWindow::wrap(v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
 {
     ASSERT_NOT_REACHED(); // LocalDOMWindow has [Custom=ToV8].
     return v8::Handle<v8::Object>();
 }
 
 } // namespace blink