Load all custom menu data.
Array of custom menu data.
function menu_load_all() {
  $custom_menus =& drupal_static(__FUNCTION__);
  if (!isset($custom_menus)) {
    if ($cached = cache('menu')
      ->get('menu_custom')) {
      $custom_menus = $cached->data;
    }
    else {
      $custom_menus = db_query('SELECT * FROM {menu_custom}')
        ->fetchAllAssoc('menu_name', PDO::FETCH_ASSOC);
      cache('menu')
        ->set('menu_custom', $custom_menus);
    }
  }
  return $custom_menus;
}