update dbus launch code in xfce4-session

Submitted by Yves-Alexis Perez

Assigned to Xfce Bug Triage

Link to original bug (#12801)

Description

Hi,

I just had a bug report from the dbus Debian maintainers, saying that dbus-launch was somehow considered deprecated. There's a lengthy explanation in https://lists.debian.org/debian-devel/2016/08/msg00554.html and in the downstream bug report (http://bugs.debian.org/836061) they indicate that the same bug will be filed against gnome-session (which might share some code with xfce4-session), so it's worth looking there too.

There's some fallback code which should continue to work, but as I understand it it won't work forever so it might make sense to migrate at one point.

If you need more info please ask, although I have to admit my own knowledge on this is pretty limited.

Version: Unspecified