Report nav timing 2 instance as soon as it's requested.

third_party/WebKit/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 1477 matching lines @@
         documentLoader->fetcher()->countPreloads())
       m_unusedPreloadsTimer.startOneShot(unusedPreloadTimeoutInSeconds,
                                          BLINK_FROM_HERE);
   } else {
     dispatchEvent(loadEvent, document());
   }
 
   if (frame()) {
     Performance* performance = DOMWindowPerformance::performance(*this);
     DCHECK(performance);
-    performance->addNavigationTiming(frame());
+    performance->notifyNavigationTimingToObservers();
   }
 
   // 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();
 
   TRACE_EVENT_INSTANT1("devtools.timeline", "MarkLoad",
@@ skipping 147 matching lines @@
   DOMWindow::trace(visitor);
   Supplementable<LocalDOMWindow>::trace(visitor);
 }
 
 DEFINE_TRACE_WRAPPERS(LocalDOMWindow) {
   visitor->traceWrappers(m_customElements);
   DOMWindow::traceWrappers(visitor);
 }
 
 }  // namespace blink