regression from
    commit e9c74a07
    drop ErrCode::GetRest

Change-Id: I937478dbc9dd217255dc5cdecb6cf66d55394cba
Reviewed-on: https://gerrit.libreoffice.org/53153Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>