Please support org.freedesktop.DisplayManager.Seat SwitchToGreeter

Submitted by Mathieu Parent

Link to original bug (#745938)

Description

LightDM and other DM use org.freedesktop.DisplayManager.Seat SwitchToGreeter on system Bus to go to greeter, GDM only supports org.gnome.DisplayManager.LocalDisplayFactory CreateTransientDisplay.

Using the same API will help interoperability.

I will try to propose a patch.