docs: JcrNodeDefinition getRootNodeDefinition() throws NoSuchNodeTypeException, RepositoryException {
          NodeTypes nodeTypes = nodeTypes();
          for (NodeDefinition definition : nodeTypes.getNodeType(ModeShapeLexicon.ROOT).getChildNodeDefinitions()) {
              if (definition.getName().equals(JcrNodeType.RESIDUAL_ITEM_NAME)) return (JcrNodeDefinition)definition;
          }
  
          assert false; // should not get here
          return null;
      }