Oilpan: Replace most of RefPtrs for Event objects with oilpan's transition types

Source/core/animation/css/CSSAnimations.cpp

Index: Source/core/animation/css/CSSAnimations.cpp
diff --git a/Source/core/animation/css/CSSAnimations.cpp b/Source/core/animation/css/CSSAnimations.cpp
index 568c917cb695a38bda29678a9626d2d1e1c2ec40..b1da2faab24fc42ac886a8d6db235f64bd2f0631 100644
--- a/Source/core/animation/css/CSSAnimations.cpp
+++ b/Source/core/animation/css/CSSAnimations.cpp
@@ -646,7 +646,7 @@ void CSSAnimations::calculateTransitionActiveInterpolations(CSSAnimationUpdate*
 void CSSAnimations::AnimationEventDelegate::maybeDispatch(Document::ListenerType listenerType, const AtomicString& eventName, double elapsedTime)
 {
     if (m_target->document().hasListenerType(listenerType)) {
-        RefPtr<WebKitAnimationEvent> event = WebKitAnimationEvent::create(eventName, m_name, elapsedTime);
+        RefPtrWillBeRawPtr<WebKitAnimationEvent> event = WebKitAnimationEvent::create(eventName, m_name, elapsedTime);
         event->setTarget(m_target);
         m_target->document().enqueueAnimationFrameEvent(event);
     }
@@ -690,7 +690,7 @@ void CSSAnimations::TransitionEventDelegate::onEventCondition(const TimedItem* t
         double elapsedTime = timing.iterationDuration;
         const AtomicString& eventType = EventTypeNames::transitionend;
         String pseudoElement = PseudoElement::pseudoElementNameForEvents(m_target->pseudoId());
-        RefPtr<TransitionEvent> event = TransitionEvent::create(eventType, propertyName, elapsedTime, pseudoElement);
+        RefPtrWillBeRawPtr<TransitionEvent> event = TransitionEvent::create(eventType, propertyName, elapsedTime, pseudoElement);
         event->setTarget(m_target);
         m_target->document().enqueueAnimationFrameEvent(event);
     }