Oilpan: Move AnimatableValue's hierarchy to oilpan's heap

Source/core/animation/AnimatableLengthBox.cpp

Index: Source/core/animation/AnimatableLengthBox.cpp
diff --git a/Source/core/animation/AnimatableLengthBox.cpp b/Source/core/animation/AnimatableLengthBox.cpp
index 825a13516555354fd44919c1bc6e8063d7e15015..ce9da370df3e89e4461d9f603b2dc5f85147400f 100644
--- a/Source/core/animation/AnimatableLengthBox.cpp
+++ b/Source/core/animation/AnimatableLengthBox.cpp
@@ -33,7 +33,7 @@
 
 namespace WebCore {
 
-PassRefPtr<AnimatableValue> AnimatableLengthBox::interpolateTo(const AnimatableValue* value, double fraction) const
+PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableLengthBox::interpolateTo(const AnimatableValue* value, double fraction) const
 {
     const AnimatableLengthBox* lengthBox = toAnimatableLengthBox(value);
     return AnimatableLengthBox::create(
@@ -43,7 +43,7 @@ PassRefPtr<AnimatableValue> AnimatableLengthBox::interpolateTo(const AnimatableV
         AnimatableValue::interpolate(this->bottom(), lengthBox->bottom(), fraction));
 }
 
-PassRefPtr<AnimatableValue> AnimatableLengthBox::addWith(const AnimatableValue* value) const
+PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableLengthBox::addWith(const AnimatableValue* value) const
 {
     const AnimatableLengthBox* lengthBox = toAnimatableLengthBox(value);
     return AnimatableLengthBox::create(
@@ -62,4 +62,12 @@ bool AnimatableLengthBox::equalTo(const AnimatableValue* value) const
         && bottom()->equals(lengthBox->bottom());
 }
 
+void AnimatableLengthBox::trace(Visitor* visitor)
+{
+    visitor->trace(m_left);
+    visitor->trace(m_right);
+    visitor->trace(m_top);
+    visitor->trace(m_bottom);
+}
+
 }