presto-hive/src/main/java/io/prestosql/plugin/hive/security/SqlStandardAccessControlMetadata.java/SqlStandardAccessControlMetadata/createRole
class SqlStandardAccessControlMetadata:    @Override
    public void createRole(ConnectorSession session, String role, Optional<HivePrincipal> grantor)
    {
        checkRoleIsNotReserved(role);
        metastore.createRole(role, null);
    }