Oilpan: Move CSSTimingData back to off-heap

Source/core/animation/css/CSSTimingData.h

Index: Source/core/animation/css/CSSTimingData.h
diff --git a/Source/core/animation/css/CSSTimingData.h b/Source/core/animation/css/CSSTimingData.h
index a2c649ca34f66a7a09c82129c51ef939edaf8a71..0ddf73ae019a6729f6aa1c0d261d9c9caf276751 100644
--- a/Source/core/animation/css/CSSTimingData.h
+++ b/Source/core/animation/css/CSSTimingData.h
@@ -13,12 +13,10 @@ namespace blink {
 
 struct Timing;
 
-class CSSTimingData : public NoBaseWillBeGarbageCollectedFinalized<CSSTimingData> {
+class CSSTimingData {
 public:
     ~CSSTimingData() { }
 
-    void trace(Visitor*) { }
-
     const Vector<double>& delayList() const { return m_delayList; }
     const Vector<double>& durationList() const { return m_durationList; }
     const Vector<RefPtr<TimingFunction> >& timingFunctionList() const { return m_timingFunctionList; }