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

Source/core/animation/animatable/AnimatableLengthBox.h

Index: Source/core/animation/animatable/AnimatableLengthBox.h
diff --git a/Source/core/animation/animatable/AnimatableLengthBox.h b/Source/core/animation/animatable/AnimatableLengthBox.h
index c93688e9f73ce7ccadbf5983b41434bfcc4b3b9d..a3953817ad2c7623fb1a6eab12af7aa75405e809 100644
--- a/Source/core/animation/animatable/AnimatableLengthBox.h
+++ b/Source/core/animation/animatable/AnimatableLengthBox.h
@@ -38,9 +38,9 @@ namespace blink {
 class AnimatableLengthBox final : public AnimatableValue {
 public:
     virtual ~AnimatableLengthBox() { }
-    static PassRefPtrWillBeRawPtr<AnimatableLengthBox> create(PassRefPtrWillBeRawPtr<AnimatableValue> left, PassRefPtrWillBeRawPtr<AnimatableValue> right, PassRefPtrWillBeRawPtr<AnimatableValue> top, PassRefPtrWillBeRawPtr<AnimatableValue> bottom)
+    static AnimatableLengthBox* create(AnimatableValue* left, AnimatableValue* right, AnimatableValue* top, AnimatableValue* bottom)
     {
-        return adoptRefWillBeNoop(new AnimatableLengthBox(left, right, top, bottom));
+        return new AnimatableLengthBox(left, right, top, bottom);
     }
     const AnimatableValue* left() const { return m_left.get(); }
     const AnimatableValue* right() const { return m_right.get(); }
@@ -50,10 +50,10 @@ public:
     DECLARE_VIRTUAL_TRACE();
 
 protected:
-    virtual PassRefPtrWillBeRawPtr<AnimatableValue> interpolateTo(const AnimatableValue*, double fraction) const override;
+    virtual AnimatableValue* interpolateTo(const AnimatableValue*, double fraction) const override;
 
 private:
-    AnimatableLengthBox(PassRefPtrWillBeRawPtr<AnimatableValue> left, PassRefPtrWillBeRawPtr<AnimatableValue> right, PassRefPtrWillBeRawPtr<AnimatableValue> top, PassRefPtrWillBeRawPtr<AnimatableValue> bottom)
+    AnimatableLengthBox(AnimatableValue* left, AnimatableValue* right, AnimatableValue* top, AnimatableValue* bottom)
         : m_left(left)
         , m_right(right)
         , m_top(top)
@@ -63,10 +63,10 @@ private:
     virtual AnimatableType type() const override { return TypeLengthBox; }
     virtual bool equalTo(const AnimatableValue*) const override;
 
-    RefPtrWillBeMember<AnimatableValue> m_left;
-    RefPtrWillBeMember<AnimatableValue> m_right;
-    RefPtrWillBeMember<AnimatableValue> m_top;
-    RefPtrWillBeMember<AnimatableValue> m_bottom;
+    Member<AnimatableValue> m_left;
+    Member<AnimatableValue> m_right;
+    Member<AnimatableValue> m_top;
+    Member<AnimatableValue> m_bottom;
 };
 
 DEFINE_ANIMATABLE_VALUE_TYPE_CASTS(AnimatableLengthBox, isLengthBox());