Fixed a forgotten null pointer protection.
Fixed a forgotten null pointer protection.

drolbr/Overpass-API,drolbr/Overpass-API,drolbr/Overpass-API,drolbr/Overpass-API,drolbr/Overpass-API,mmd-osm/Overpass-API,mmd-osm/Overpass-API,mmd-osm/Overpass-API,mmd-osm/Overpass-API,drolbr/Overpass-API