instead of randomly defining it in only some of .src files

Change-Id: Ifec3920740723d248400f451d717b5288c421b8d
Reviewed-on: https://gerrit.libreoffice.org/36832Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>