presto-hive/src/main/java/io/prestosql/plugin/hive/metastore/file/FileHiveMetastore.java/FileHiveMetastore/writeRoleGrantsFile
class FileHiveMetastore:    private void writeRoleGrantsFile(Set<RoleGrant> roleGrants)
    {
        writeFile("roleGrants", getRoleGrantsFile(), roleGrantsCodec, ImmutableList.copyOf(roleGrants), true);
    }