Introduce DEFINE_ANIMATABLE_VALUE_TYPE_CASTS to replace manual toFoo() for animatable value

Source/core/animation/AnimatableStrokeDasharrayList.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 43 matching lines @@
     AnimatableStrokeDasharrayList(const Vector<SVGLength>&);
     // This will consume the vector passed into it.
     AnimatableStrokeDasharrayList(Vector<RefPtr<AnimatableValue> >& values)
         : AnimatableRepeatable(values)
     {
     }
 
     virtual AnimatableType type() const { return TypeStrokeDasharrayList; }
 };
 
-inline const AnimatableStrokeDasharrayList* toAnimatableStrokeDasharrayList(const AnimatableValue* value)
-{
-    ASSERT_WITH_SECURITY_IMPLICATION(value && value->isStrokeDasharrayList());
-    return static_cast<const AnimatableStrokeDasharrayList*>(value);
-}
+DEFINE_ANIMATABLE_VALUE_TYPE_CASTS(AnimatableStrokeDasharrayList, isStrokeDasharrayList());
 
 } // namespace WebCore
 
 #endif // AnimatableStrokeDasharrayList_h