Trace where timers were scheduled in Blink

Source/core/html/HTMLSourceElement.cpp

 /*
  * Copyright (C) 2007, 2008, 2010 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 83 matching lines @@
 {
     setAttribute(typeAttr, type);
 }
 
 void HTMLSourceElement::scheduleErrorEvent()
 {
     WTF_LOG(Media, "HTMLSourceElement::scheduleErrorEvent - %p", this);
     if (m_errorEventTimer.isActive())
         return;
 
-    m_errorEventTimer.startOneShot(0);
+    m_errorEventTimer.startOneShot(0, FROM_HERE);
 }
 
 void HTMLSourceElement::cancelPendingErrorEvent()
 {
     WTF_LOG(Media, "HTMLSourceElement::cancelPendingErrorEvent - %p", this);
     m_errorEventTimer.stop();
 }
 
 void HTMLSourceElement::errorEventTimerFired(Timer<HTMLSourceElement>*)
 {
     WTF_LOG(Media, "HTMLSourceElement::errorEventTimerFired - %p", this);
     dispatchEvent(Event::createCancelable(EventTypeNames::error));
 }
 
 bool HTMLSourceElement::isURLAttribute(const Attribute& attribute) const
 {
     return attribute.name() == srcAttr || HTMLElement::isURLAttribute(attribute);
 }
 
 }