serializedFields example

if (!isset($link[$name])) {
        $link[$name] = $default;
      }
    }
    $fields = array_intersect_key($link, $schema_fields);
    // Sort the route parameters so that the query string will be the same.     asort($fields['route_parameters']);
    // Since this will be urlencoded, it's safe to store and match against a     // text field.     $fields['route_param_key'] = $fields['route_parameters'] ? UrlHelper::buildQuery($fields['route_parameters']) : '';

    foreach ($this->serializedFields() as $name) {
      if (isset($fields[$name])) {
        $fields[$name] = serialize($fields[$name]);
      }
    }
    $this->setParents($fields, $parent, $original);

    // Need to check both parent and menu_name, since parent can be empty in any     // menu.     if ($original && ($link['parent'] != $original['parent'] || $link['menu_name'] != $original['menu_name'])) {
      $this->moveChildren($fields, $original);
    }