Trace where timers were scheduled in Blink

Source/core/dom/CSSSelectorWatch.cpp

 /*
  * Copyright (C) 2013 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 51 matching lines @@
     return *watch;
 }
 
 void CSSSelectorWatch::callbackSelectorChangeTimerFired(Timer<CSSSelectorWatch>*)
 {
     // Should be ensured by updateSelectorMatches():
     ASSERT(!m_addedSelectors.isEmpty() || !m_removedSelectors.isEmpty());
 
     if (m_timerExpirations < 1) {
         m_timerExpirations++;
-        m_callbackSelectorChangeTimer.startOneShot(0);
+        m_callbackSelectorChangeTimer.startOneShot(0, FROM_HERE);
         return;
     }
     if (m_document.frame()) {
         Vector<String> addedSelectors;
         Vector<String> removedSelectors;
         copyToVector(m_addedSelectors, addedSelectors);
         copyToVector(m_removedSelectors, removedSelectors);
         m_document.frame()->loader().client()->selectorMatchChanged(addedSelectors, removedSelectors);
     }
     m_addedSelectors.clear();
@@ skipping 35 matching lines @@
         return;
 
     if (m_removedSelectors.isEmpty() && m_addedSelectors.isEmpty()) {
         if (m_callbackSelectorChangeTimer.isActive()) {
             m_timerExpirations = 0;
             m_callbackSelectorChangeTimer.stop();
         }
     } else {
         m_timerExpirations = 0;
         if (!m_callbackSelectorChangeTimer.isActive())
-            m_callbackSelectorChangeTimer.startOneShot(0);
+            m_callbackSelectorChangeTimer.startOneShot(0, FROM_HERE);
     }
 }
 
 static bool allCompound(const CSSSelectorList& selectorList)
 {
     for (const CSSSelector* selector = selectorList.first(); selector; selector = selectorList.next(*selector)) {
         if (!selector->isCompound())
             return false;
     }
     return true;
@@ skipping 19 matching lines @@
 
         RefPtrWillBeRawPtr<StyleRule> rule = StyleRule::create();
         rule->wrapperAdoptSelectorList(selectorList);
         rule->setProperties(callbackPropertySet);
         m_watchedCallbackSelectors.append(rule.release());
     }
     m_document.changedSelectorWatch();
 }
 
 } // namespace WebCore