Creates an element upgrader which can be used to change the Dart wrapper /// type for elements. /// /// The type specified must be a subclass of HtmlElement, when an element is /// upgraded then the created constructor will be invoked on that element. /// /// If the type is not a direct subclass of HtmlElement then the extendsTag /// parameter must be provided.

Source

@Experimental()
ElementUpgrader createElementUpgrader(Type type, {String extendsTag}) {
  return new _VMElementUpgrader(this, type, extendsTag);
}