I'm not able to reproduce this, and from the logs you've posted it looks like lightdm aborts well before the new gnome-desktop codepath is reached. Could you please try upgrading back to libgnome-desktop-3-2 3.2.0-0ubuntu2 to see whether this was caused by an unrelated issue that got fixed with a package install?
I'm not able to reproduce this, and from the logs you've posted it looks like lightdm aborts well before the new gnome-desktop codepath is reached. Could you please try upgrading back to libgnome- desktop- 3-2 3.2.0-0ubuntu2 to see whether this was caused by an unrelated issue that got fixed with a package install?