unity-greeter crashed with signal 5 in g_object_newv()

[Norbert Kiesel]

this resulted in X not starting (also not in failsafe more).

Ultimate solution was to run "glib-compile-schemas /usr/share/glib-2.0/schemas" followed by "service lightdm start", but it took me quite a while to figure that out.

Other (unrelated) problems discovered while debugging this:
- greeters use /usr/share/backgrounds/warty-final-ubuntu.png, which is not a png (it's a jpeg)
- unity-greeter looks for /usr/lib/at-spi2-core instead of /usr/lib/x86_64-linux-gnu/at-spi2-core
- /usr/share/xdiagnose/failsafeXServer crashes at line 87 because "last_run=$(tail -n 1 $failsafe_log | cut -d' ' -f1)" just above that line does not return a number

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: overlay-scrollbar 0.2.16-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-22.35-generic 3.2.14
Uname: Linux 3.2.0-22-generic x86_64
ApportVersion: 2.0-0ubuntu4
Architecture: amd64
CrashCounter: 1
Date: Wed Apr 4 18:51:14 2012
ExecutablePath: /usr/sbin/unity-greeter
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
PackageArchitecture: all
ProcCmdline: /usr/sbin/unity-greeter
ProcEnviron:
 SHELL=/bin/bash
 TERM=linux
 PATH=(custom, no user)
 LANG=en_US.UTF-8
Signal: 5
SourcePackage: overlay-scrollbar
Title: unity-greeter crashed with signal 5 in g_object_newv()
UpgradeStatus: Upgraded to precise on 2012-03-31 (4 days ago)
UserGroups:

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #932308, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.