[Oilpan] Migrate most classes under core/animations to Oilpan heap.

Source/core/animation/ElementAnimations.h

Index: Source/core/animation/ElementAnimations.h
diff --git a/Source/core/animation/ElementAnimations.h b/Source/core/animation/ElementAnimations.h
index bc2607d976ea029077e9f7f4ff7bc863ce302002..ad23910b4660368fedecd2d88044ceba8e14e043 100644
--- a/Source/core/animation/ElementAnimations.h
+++ b/Source/core/animation/ElementAnimations.h
@@ -44,11 +44,13 @@ class CSSAnimations;
 
 using AnimationCountedSet = WillBeHeapHashCountedSet<RawPtrWillBeWeakMember<Animation>>;
 
-class ElementAnimations : public NoBaseWillBeGarbageCollectedFinalized<ElementAnimations> {
+class ElementAnimations : public GarbageCollectedFinalized<ElementAnimations> {
     WTF_MAKE_NONCOPYABLE(ElementAnimations);
+    USING_PRE_FINALIZER(ElementAnimations, dispose);
 public:
     ElementAnimations();
     ~ElementAnimations();
+    void dispose();
 
     // Animations that are currently active for this element, their effects will be applied
     // during a style recalc. CSS Transitions are included in this stack.
@@ -93,7 +95,7 @@ private:
 #if !ENABLE(OILPAN)
     // FIXME: Oilpan: This is to avoid a reference cycle that keeps Elements alive
     // and won't be needed once the Node hierarchy becomes traceable.
-    Vector<KeyframeEffect*> m_effects;
+    HeapVector<Member<KeyframeEffect>> m_effects;
 #endif
 
     // CSSAnimations and DeferredLegacyStyleInterpolation checks if a style change is due to animation.