GetNewObjectId question

While browsing through varsup.c, I noticed this comment on GetNewObjectId:

* Hence, this routine should generally not be used directly. The only direct
* callers should be GetNewOidWithIndex() and GetNewRelFileNumber() in
* catalog/catalog.c.

But AddRoleMems in user.c appears to also call the function directly:

/* get an OID for the new row and insert it */
objectId = GetNewObjectId();
new_record[Anum_pg_auth_members_oid - 1] = objectId;
tuple = heap_form_tuple(pg_authmem_dsc,
new_record, new_record_nulls);
CatalogTupleInsert(pg_authmem_rel, tuple);

I'm not sure if that call is right, but this seems inconsistent.
Should that caller be using GetNewOidWithIndex instead? Or should the
comment be updated?

Thanks,
Maciek