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

Source/core/animation/LegacyStyleInterpolation.h

Index: Source/core/animation/LegacyStyleInterpolation.h
diff --git a/Source/core/animation/LegacyStyleInterpolation.h b/Source/core/animation/LegacyStyleInterpolation.h
index aceb97d6b844261d3dcc71dbf68058b6e8102aa7..45afafa22ddaae510ad35513ddc0c862418ce7ab 100644
--- a/Source/core/animation/LegacyStyleInterpolation.h
+++ b/Source/core/animation/LegacyStyleInterpolation.h
@@ -12,20 +12,20 @@ namespace blink {
 
 class LegacyStyleInterpolation : public StyleInterpolation {
 public:
-    static PassRefPtrWillBeRawPtr<LegacyStyleInterpolation> create(PassRefPtrWillBeRawPtr<AnimatableValue> start, PassRefPtrWillBeRawPtr<AnimatableValue> end, CSSPropertyID id)
+    static LegacyStyleInterpolation* create(AnimatableValue* start, AnimatableValue* end, CSSPropertyID id)
     {
-        return adoptRefWillBeNoop(new LegacyStyleInterpolation(InterpolableAnimatableValue::create(start), InterpolableAnimatableValue::create(end), id));
+        return new LegacyStyleInterpolation(InterpolableAnimatableValue::create(start), InterpolableAnimatableValue::create(end), id);
     }
 
     void apply(StyleResolverState& state) const override
     {
-        AnimatedStyleBuilder::applyProperty(m_id, state, currentValue().get());
+        AnimatedStyleBuilder::applyProperty(m_id, state, currentValue());
     }
 
     bool isLegacyStyleInterpolation() const final { return true; }
-    PassRefPtrWillBeRawPtr<AnimatableValue> currentValue() const
+    AnimatableValue* currentValue() const
     {
-        return toInterpolableAnimatableValue(m_cachedValue.get())->value();
+        return toInterpolableAnimatableValue(m_cachedValue)->value();
     }
 
     DEFINE_INLINE_VIRTUAL_TRACE()
@@ -34,7 +34,7 @@ public:
     }
 
 private:
-    LegacyStyleInterpolation(PassOwnPtrWillBeRawPtr<InterpolableValue> start, PassOwnPtrWillBeRawPtr<InterpolableValue> end, CSSPropertyID id)
+    LegacyStyleInterpolation(InterpolableValue* start, InterpolableValue* end, CSSPropertyID id)
         : StyleInterpolation(start, end, id)
     {
     }