Oilpan: Fix tracing of events through XMLHttpRequestProgressEventThrottle.

Source/core/xml/XMLHttpRequestProgressEventThrottle.h

 /*
  * Copyright (C) 2010 Julien Chaffraix <jchaffraix@webkit.org>
  * All right 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
@@ skipping 29 matching lines @@
 
 enum ProgressEventAction {
     DoNotFlushProgressEvent,
     FlushDeferredProgressEvent,
     FlushProgressEvent
 };
 
 // This implements the XHR2 progress event dispatching: "dispatch a progress event called progress
 // about every 50ms or for every byte received, whichever is least frequent".
 class XMLHttpRequestProgressEventThrottle FINAL : public TimerBase {
+    DISALLOW_ALLOCATION();
 public:
     explicit XMLHttpRequestProgressEventThrottle(EventTarget*);
     virtual ~XMLHttpRequestProgressEventThrottle();
 
     void dispatchProgressEvent(bool lengthComputable, unsigned long long loaded, unsigned long long total);
     void dispatchReadyStateChangeEvent(PassRefPtrWillBeRawPtr<Event>, ProgressEventAction = DoNotFlushProgressEvent);
     void dispatchEvent(PassRefPtrWillBeRawPtr<Event>);
     void dispatchEventAndLoadEnd(const AtomicString&, bool, unsigned long long, unsigned long long);
 
     void suspend();
     void resume();
 
+    void trace(Visitor*);
+
 private:
     static const double minimumProgressEventDispatchingIntervalInSeconds;
 
     virtual void fired() OVERRIDE;
     void dispatchDeferredEvents(Timer<XMLHttpRequestProgressEventThrottle>*);
     bool flushDeferredProgressEvent();
     void deliverProgressEvent();
 
     bool hasEventToDispatch() const;
 
     // Weak pointer to our XMLHttpRequest object as it is the one holding us.
     EventTarget* m_target;
 
     bool m_lengthComputable;
     unsigned long long m_loaded;
     unsigned long long m_total;
 
     bool m_deferEvents;
-    RefPtrWillBePersistent<Event> m_deferredProgressEvent;
-    WillBePersistentHeapVector<RefPtrWillBeMember<Event> > m_deferredEvents;
+    RefPtrWillBeMember<Event> m_deferredProgressEvent;
+    WillBeHeapVector<RefPtrWillBeMember<Event> > m_deferredEvents;
     Timer<XMLHttpRequestProgressEventThrottle> m_dispatchDeferredEventsTimer;
 };
 
 } // namespace WebCore
 
 #endif // XMLHttpRequestProgressEventThrottle_h