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

Source/core/animation/animatable/AnimatableShapeValue.h

Index: Source/core/animation/animatable/AnimatableShapeValue.h
diff --git a/Source/core/animation/animatable/AnimatableShapeValue.h b/Source/core/animation/animatable/AnimatableShapeValue.h
index 026082914db429d2bb546ee830d94945e982c75a..c58a434f90b9bbedc288006f542e3508c36ace5b 100644
--- a/Source/core/animation/animatable/AnimatableShapeValue.h
+++ b/Source/core/animation/animatable/AnimatableShapeValue.h
@@ -40,16 +40,16 @@ namespace blink {
 class CORE_EXPORT AnimatableShapeValue final : public AnimatableValue {
 public:
     ~AnimatableShapeValue() override { }
-    static PassRefPtrWillBeRawPtr<AnimatableShapeValue> create(ShapeValue* shape)
+    static AnimatableShapeValue* create(ShapeValue* shape)
     {
-        return adoptRefWillBeNoop(new AnimatableShapeValue(shape));
+        return new AnimatableShapeValue(shape);
     }
     ShapeValue* shapeValue() const { return m_shape.get(); }
 
     DECLARE_VIRTUAL_TRACE();
 
 protected:
-    PassRefPtrWillBeRawPtr<AnimatableValue> interpolateTo(const AnimatableValue*, double fraction) const override;
+    AnimatableValue* interpolateTo(const AnimatableValue*, double fraction) const override;
     bool usesDefaultInterpolationWith(const AnimatableValue*) const override;
 
 private: