anchor.diff:    Element remove(Element el) {
       return el..remove();
     }
  -  insertBefore(Node el, node) {
  +  void insertBefore(Node el, node) {
       el.parentNode.insertBefore(node, el);
     }
     void insertAllBefore(Node el, Iterable<Node> nodes) {
  
positive.code:   }
    MouseEvent createMouseEvent(String eventType) =>
        new MouseEvent(eventType, canBubble: true);
    createEvent(eventType) => new Event(eventType, canBubble: true);
    String getInnerHTML(Element el) => el.innerHtml;
    String getOuterHTML(Element el) => el.outerHtml;
    void setInnerHTML(Element el, String value) {
  
negative.code:     if (doc == null) doc = document;
      return doc.createElement(tagName);
    }
    Text createTextNode(String text, [HtmlDocument doc = null]) {
      return new Text(text);
    }
    createScriptTag(String attrName, String attrValue,
  