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

Source/core/animation/animatable/AnimatableFilterOperations.h

Index: Source/core/animation/animatable/AnimatableFilterOperations.h
diff --git a/Source/core/animation/animatable/AnimatableFilterOperations.h b/Source/core/animation/animatable/AnimatableFilterOperations.h
index a2e59197eeb3e27297d56e5033eceace5b405279..957fdf3997e4822fd068cc505eb69112a7b5d700 100644
--- a/Source/core/animation/animatable/AnimatableFilterOperations.h
+++ b/Source/core/animation/animatable/AnimatableFilterOperations.h
@@ -38,9 +38,9 @@ namespace blink {
 
 class AnimatableFilterOperations final : public AnimatableValue {
 public:
-    static PassRefPtrWillBeRawPtr<AnimatableFilterOperations> create(const FilterOperations& operations)
+    static AnimatableFilterOperations* create(const FilterOperations& operations)
     {
-        return adoptRefWillBeNoop(new AnimatableFilterOperations(operations));
+        return new AnimatableFilterOperations(operations);
     }
 
     virtual ~AnimatableFilterOperations() { }
@@ -49,7 +49,7 @@ public:
     const FilterOperations& operations() const { return m_operations; }
 
 protected:
-    virtual PassRefPtrWillBeRawPtr<AnimatableValue> interpolateTo(const AnimatableValue*, double fraction) const override;
+    virtual AnimatableValue* interpolateTo(const AnimatableValue*, double fraction) const override;
     virtual bool usesDefaultInterpolationWith(const AnimatableValue*) const override;
 
 private: