anchor.diff:    JsObject get customStyle => this["customStyle"];
   }
   
  -typedef PolymerElement DartConstructor(HtmlElement element);
  -Map<String, Function> constructorFromString = {};
  
positive.code:         [tagName, jsConstructor]);
    }
  
    // TODO add tests
    static JsFunction call(Map constructor) =>
        context.callMethod("Polymer", [jsify(constructor)]);
  
    // TODO add tests
    static JsFunction Class(Map constructor) =>
        context["Polymer"].callMethod("Class", [jsify(constructor)]);
  
  
negative.code:   /// such as adding or removing classes in this element's local DOM.
    static updateStyles() => context["Polymer"].callMethod("updateStyles");
  }
  
  
  class WebElement extends Object with JsMixin {
    final HtmlElement element;
  