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

Source/core/animation/ImageSliceStyleInterpolation.cpp

Index: Source/core/animation/ImageSliceStyleInterpolation.cpp
diff --git a/Source/core/animation/ImageSliceStyleInterpolation.cpp b/Source/core/animation/ImageSliceStyleInterpolation.cpp
index ad46bc372f4a1772d3c1d8c138ca0fcf9396871e..79f016e4fa97fede51a03505c0dd3a4a0d3c9ac2 100644
--- a/Source/core/animation/ImageSliceStyleInterpolation.cpp
+++ b/Source/core/animation/ImageSliceStyleInterpolation.cpp
@@ -32,14 +32,14 @@ public:
         decompose(value);
     }
 
-    OwnPtrWillBeMember<InterpolableValue> interpolableValue;
+    Member<InterpolableValue> interpolableValue;
     ImageSliceStyleInterpolation::Metadata metadata;
 
 private:
     void decompose(const CSSBorderImageSliceValue& value)
     {
         const size_t kQuadSides = 4;
-        OwnPtrWillBeRawPtr<InterpolableList> interpolableList = InterpolableList::create(kQuadSides);
+        InterpolableList* interpolableList = InterpolableList::create(kQuadSides);
         const Quad& quad = *value.slices();
         interpolableList->set(0, InterpolableNumber::create(quad.top()->getDoubleValue()));
         interpolableList->set(1, InterpolableNumber::create(quad.right()->getDoubleValue()));
@@ -50,7 +50,7 @@ private:
             && quad.left()->isPercentage() == isPercentage
             && quad.right()->isPercentage() == isPercentage);
 
-        interpolableValue = interpolableList.release();
+        interpolableValue = interpolableList;
         metadata = ImageSliceStyleInterpolation::Metadata {isPercentage, value.m_fill};
     }
 };
@@ -69,7 +69,7 @@ PassRefPtrWillBeRawPtr<CSSBorderImageSliceValue> compose(const InterpolableValue
 
 } // namespace
 
-PassRefPtrWillBeRawPtr<ImageSliceStyleInterpolation> ImageSliceStyleInterpolation::maybeCreate(const CSSValue& start, const CSSValue& end, CSSPropertyID property)
+ImageSliceStyleInterpolation* ImageSliceStyleInterpolation::maybeCreate(const CSSValue& start, const CSSValue& end, CSSPropertyID property)
 {
     if (!start.isBorderImageSliceValue() || !end.isBorderImageSliceValue())
         return nullptr;
@@ -79,12 +79,7 @@ PassRefPtrWillBeRawPtr<ImageSliceStyleInterpolation> ImageSliceStyleInterpolatio
     if (!(startDecompose.metadata == endDecompose.metadata))
         return nullptr;
 
-    return adoptRefWillBeNoop(new ImageSliceStyleInterpolation(
-        startDecompose.interpolableValue.release(),
-        endDecompose.interpolableValue.release(),
-        property,
-        startDecompose.metadata
-    ));
+    return new ImageSliceStyleInterpolation(startDecompose.interpolableValue.release(), endDecompose.interpolableValue.release(), property, startDecompose.metadata);
 }
 
 void ImageSliceStyleInterpolation::apply(StyleResolverState& state) const