Only communicate CSSPrimitiveValue references from SVGLength

third_party/WebKit/Source/core/svg/SVGAnimatedLength.h

 /*
  * Copyright (C) 2014 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 36 matching lines @@
       const QualifiedName& attributeName,
       SVGLength* initialValue,
       CSSPropertyID cssPropertyId = CSSPropertyInvalid) {
     return new SVGAnimatedLength(contextElement, attributeName, initialValue,
                                  cssPropertyId);
   }
 
   void setDefaultValueAsString(const String&);
   SVGParsingError setBaseValueAsString(const String&) override;
 
+  const CSSValue* cssValue() const {
+    return &currentValue()->asCSSPrimitiveValue();
+  }
+
   DECLARE_VIRTUAL_TRACE_WRAPPERS();
 
  protected:
   SVGAnimatedLength(SVGElement* contextElement,
                     const QualifiedName& attributeName,
                     SVGLength* initialValue,
                     CSSPropertyID cssPropertyId = CSSPropertyInvalid)
       : SVGAnimatedProperty<SVGLength>(contextElement,
                                        attributeName,
                                        initialValue,
                                        cssPropertyId) {}
 };
 
 }  // namespace blink
 
 #endif  // SVGAnimatedLength_h