presto-hive/src/main/java/io/prestosql/plugin/hive/metastore/cache/CachingHiveMetastore.java/CachingHiveMetastore/listRoleGrants
class CachingHiveMetastore:    @Override
    public Set<RoleGrant> listRoleGrants(HivePrincipal principal)
    {
        return get(roleGrantsCache, principal);
    }