action buttons should use DBus to switch between users

Submitted by Guido Berhoerster

Assigned to Nick Schermer

Link to original bug (#9307)

Description

The action buttons plugin currently simply checks for the presence of the "gdmflexiserver" tool in $PATH for offering the "Switch user" item. This is rather unreliable since GDM or LightDM (which provide this tool) might be installed but not actually running (see e.g.https://bugzilla.novell.com/show_bug.cgi?id=780707 ). There should be an additional check for the running display manager which could be implemented through DBus and/or environment variables.

Version: Unspecified