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

Source/core/animation/animatable/AnimatableColor.cpp

Index: Source/core/animation/animatable/AnimatableColor.cpp
diff --git a/Source/core/animation/animatable/AnimatableColor.cpp b/Source/core/animation/animatable/AnimatableColor.cpp
index 337fe3c96dc09bcdb403bd4a424079ddb1fe75f3..1c16b8a0239ea5649c7c7e102f214551ef2b374d 100644
--- a/Source/core/animation/animatable/AnimatableColor.cpp
+++ b/Source/core/animation/animatable/AnimatableColor.cpp
@@ -74,12 +74,12 @@ bool AnimatableColorImpl::operator==(const AnimatableColorImpl& other) const
         && m_alpha == other.m_alpha;
 }
 
-PassRefPtrWillBeRawPtr<AnimatableColor> AnimatableColor::create(const AnimatableColorImpl& color, const AnimatableColorImpl& visitedLinkColor)
+AnimatableColor* AnimatableColor::create(const AnimatableColorImpl& color, const AnimatableColorImpl& visitedLinkColor)
 {
-    return adoptRefWillBeNoop(new AnimatableColor(color, visitedLinkColor));
+    return new AnimatableColor(color, visitedLinkColor);
 }
 
-PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableColor::interpolateTo(const AnimatableValue* value, double fraction) const
+AnimatableValue* AnimatableColor::interpolateTo(const AnimatableValue* value, double fraction) const
 {
     const AnimatableColor* color = toAnimatableColor(value);
     return create(m_color.interpolateTo(color->m_color, fraction),