Trace where timers were scheduled in Blink

Source/core/html/track/LoadableTextTrack.cpp

 /*
  * Copyright (C) 2011 Google 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 68 matching lines @@
     }
 
     // 4.8.10.12.3 Sourcing out-of-band text tracks (continued)
 
     // 2. Let URL be the track URL of the track element.
     m_url = url;
 
     // 3. Asynchronously run the remaining steps, while continuing with whatever task
     // was responsible for creating the text track or changing the text track mode.
     if (!m_loadTimer.isActive())
-        m_loadTimer.startOneShot(0);
+        m_loadTimer.startOneShot(0, FROM_HERE);
 }
 
 void LoadableTextTrack::loadTimerFired(Timer<LoadableTextTrack>*)
 {
     if (m_loader)
         m_loader->cancelLoad();
 
     if (!m_trackElement)
         return;
 
@@ skipping 61 matching lines @@
         if (child == m_trackElement)
             return index;
         ++index;
     }
     ASSERT_NOT_REACHED();
 
     return 0;
 }
 
 } // namespace WebCore