/**
* Return unique editor instance ID
*/
public static function getInstanceId()
{
wfProfileIn(__METHOD__);
if (self::$instanceId === null) {
global $wgCityId;
$id = uniqid(mt_rand());
self::$instanceId = "{$wgCityId}-{$id}";
}
wfProfileOut(__METHOD__);
return self::$instanceId;
}