Skip non-Object tiles in UpdateObjectColours

src/object_cmd.cpp

@@ -174,6 +174,8 @@ void UpdateCompanyHQ(TileIndex tile, uint score)
 void UpdateObjectColours(const Company *c)
 {
 	for (Object *obj : Object::Iterate()) {
+		if (!IsTileType(obj->location.tile, MP_OBJECT)) continue;
+
 		Owner owner = GetTileOwner(obj->location.tile);
 		/* Not the current owner, so colour doesn't change. */
 		if (owner != c->index) continue;