_node_name returns NULL on no node types

I tried disabling page module and after this, every page shows a warning:

warning: Invalid argument supplied for foreach() in /var/www/localhost/htdocs/includes/theme.inc on line 231.

Drupal code near this line is:

  if (module_exist('node')) {
    foreach (node_get_types() as $type) {
      $defaults['toggle_node_info_' . $type] = 1;
    }
  }