code: protected void compareHasChildNodes(Node control, Node test,
                                          DifferenceListener listener) throws DifferenceFoundException {
          Boolean controlHasChildren = hasChildNodes(control);
          Boolean testHasChildren = hasChildNodes(test);
          compare(controlHasChildren, testHasChildren, control, test,
                  listener, HAS_CHILD_NODES);
      }
docs: Compare the number of children, and if the same, compare the actual
  children via their NodeLists.
  @param control
  @param test
  @param listener
  @throws DifferenceFoundException