Unlock screen uses wrong geometry when resuming from suspend in multi-display setting

[Bruno Girin]

When connecting an external screen to my laptop, when I suspend the laptop and resume, the unlock screen is presented on the laptop's main display but using the geometry of the external display.

Steps to reproduce:
1. Connect an external display that has a different resolution than the built-in laptop's display.
2. Suspend the laptop, e.g. by closing the lid.
3. Wake up the laptop.
4. The unlock screen asking for a password is displayed on the laptop's built-in display.

Expected behaviour:
The unlock screen uses the resolution of the display where it appears, i.e. the laptop's display.

Actual behaviour:
The unlock screen uses the resolution of the external display while appearing on the laptop's built-in display.
Once the password is entered, resolution reverts to what it should be.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: unity 5.10.0-0ubuntu6
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic x86_64
ApportVersion: 2.0.1-0ubuntu7
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
Date: Thu May 10 22:07:15 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Beta amd64 (20110901)
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: Upgraded to precise on 2012-02-11 (89 days ago)

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 995387, so it 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. Feel free to continue to report any other bugs you may find.