getMenuNames example

  /** * {@inheritdoc} */
  public function rebuild(array $definitions) {
    $links = [];
    $children = [];
    $top_links = [];
    // Fetch the list of existing menus, in case some are not longer populated     // after the rebuild.     $before_menus = $this->getMenuNames();
    if ($definitions) {
      foreach ($definitions as $id => $link) {
        // Flag this link as discovered, i.e. saved via rebuild().         $link['discovered'] = 1;
        // Note: The parent we set here might be just stored in the {menu_tree}         // table, so it will not end up in $top_links. Therefore the later loop         // on the orphan links, will handle those cases.         if (!empty($link['parent'])) {
          $children[$link['parent']][$id] = $id;
        }
        else {