code: function (nodes, id) {
              for (var i = 0; i < nodes.length; i++) {
                  var attrId = nodes.item(i).getAttribute("id");
                  if (!attrId) {
                      continue;
                  }
                  if (attrId.toString() === id) {
                      return nodes.item(i);
                  }
              }
              return null;
          }
docs: Finds a node by id.
  Internal. Applications should not call this function.
  @param {NodeList} nodes A list of nodes to look in.
  @param {String} id The id of the node to search for.