Fixing dart:html links _not_ found in docs.json

tools/dom/templates/html/impl/impl_Node.darttemplate

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of $LIBRARYNAME;
 
 /**
  * Lazy implementation of the child nodes of an element that does not request
  * the actual child nodes of an element until strictly necessary greatly
  * improving performance for the typical cases where it is not required.
@@ skipping 281 matching lines @@
     String value = nodeValue;  // Fetch DOM Node property once.
     return value == null ? super.toString() : value;
   }
 
 $if DARTIUM
   /**
    * A list of this node's children.
    *
    * ## Other resources
    *
-   * * [Node.childNodes]
-   * (https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
-   * from MDN.
+   * * [Node.childNodes](https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
+   *   from MDN.
    */
   @DomName('Node.childNodes')
   @DocsEditable()
   List<Node> get childNodes => wrap_jso(_blink.BlinkNode.instance.childNodes_Getter_(unwrap_jso(this)));
 $else
   /**
    * A list of this node's children.
    *
    * ## Other resources
    *
-   * * [Node.childNodes]
-   * (https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
-   * from MDN.
+   * * [Node.childNodes](https://developer.mozilla.org/en-US/docs/Web/API/Node.childNodes)
+   *   from MDN.
    */
   @DomName('Node.childNodes')
   @DocsEditable()
   @Returns('NodeList')
   @Creates('NodeList')
   final List<Node> childNodes;
 
 $endif
 $!MEMBERS
 }