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

Source/core/animation/animatable/AnimatableTransform.cpp

Index: Source/core/animation/animatable/AnimatableTransform.cpp
diff --git a/Source/core/animation/animatable/AnimatableTransform.cpp b/Source/core/animation/animatable/AnimatableTransform.cpp
index c063ccf44a7c25b40be9d4f56996f9a39e4337c6..d541949087109919c21afdd544dbab13441d96f0 100644
--- a/Source/core/animation/animatable/AnimatableTransform.cpp
+++ b/Source/core/animation/animatable/AnimatableTransform.cpp
@@ -33,12 +33,12 @@
 
 namespace blink {
 
-PassRefPtrWillBeRawPtr<AnimatableTransform> AnimatableTransform::create(const TransformOperations& transform)
+AnimatableTransform* AnimatableTransform::create(const TransformOperations& transform)
 {
-    return adoptRefWillBeNoop(new AnimatableTransform(transform));
+    return new AnimatableTransform(transform);
 }
 
-PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableTransform::interpolateTo(const AnimatableValue* value, double fraction) const
+AnimatableValue* AnimatableTransform::interpolateTo(const AnimatableValue* value, double fraction) const
 {
     const AnimatableTransform* transform = toAnimatableTransform(value);
     return AnimatableTransform::create(transform->m_transform.blend(m_transform, fraction));