Web Animations: Add CSSAnimatableValueFactory API (partial implementation)

Source/core/animation/AnimatableValue.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 23 matching lines @@
 #include "core/css/CSSValue.h"
 #include "wtf/RefCounted.h"
 
 namespace WebCore {
 
 class CSSValue;
 
 class AnimatableValue : public RefCounted<AnimatableValue> {
 public:
     virtual ~AnimatableValue() { }
-    static PassRefPtr<AnimatableValue> create(CSSValue*);
     virtual PassRefPtr<CSSValue> toCSSValue() const = 0;
 
     static const AnimatableValue* neutralValue();
     virtual bool isNeutral() const { return false; }
 
     static PassRefPtr<AnimatableValue> interpolate(const AnimatableValue*, const AnimatableValue*, double fraction);
     // For noncommutative values read add(A, B) to mean the value A with B composed onto it.
     static PassRefPtr<AnimatableValue> add(const AnimatableValue*, const AnimatableValue*);
 
 protected:
@@ skipping 20 matching lines @@
 
     template <class T>
     static PassRefPtr<T> takeConstRef(const T* value) { return PassRefPtr<T>(const_cast<T*>(value)); }
 
     AnimatableType m_type;
 };
 
 } // namespace WebCore
 
 #endif // AnimatableValue_h