Make element.style["color"] work in Sky

sky/engine/core/animation/AnimationNodeTiming.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SKY_ENGINE_CORE_ANIMATION_ANIMATIONNODETIMING_H_
 #define SKY_ENGINE_CORE_ANIMATION_ANIMATIONNODETIMING_H_
 
 #include "sky/engine/tonic/dart_wrappable.h"
 #include "sky/engine/bindings/nullable.h"
 #include "sky/engine/core/animation/AnimationNode.h"
 #include "sky/engine/wtf/RefCounted.h"
 #include "sky/engine/wtf/text/WTFString.h"
 
 namespace blink {
 
 class AnimationNodeTiming : public RefCounted<AnimationNodeTiming>, public DartWrappable {
     DEFINE_WRAPPERTYPEINFO();
 public:
     static PassRefPtr<AnimationNodeTiming> create(AnimationNode* parent);
     double delay();
     double endDelay();
     String fill();
     double iterationStart();
     double iterations();
-    void getDuration(String propertyName, Nullable<double>& element0, String& element1);
+    String getDuration(String propertyName);
     double playbackRate();
     String direction();
     String easing();
 
     void setDelay(double);
     void setEndDelay(double);
     void setFill(String);
     void setIterationStart(double);
     void setIterations(double);
     bool setDuration(String name, double duration);
     void setPlaybackRate(double);
     void setDirection(String);
     void setEasing(String);
 
 private:
     RefPtr<AnimationNode> m_parent;
     explicit AnimationNodeTiming(AnimationNode*);
 };
 
 } // namespace blink
 
 #endif  // SKY_ENGINE_CORE_ANIMATION_ANIMATIONNODETIMING_H_