[regression] Windows are not drawn when resuming from locked screen

[Ingo Gerth]

When unlocking the screen, any window that is restored from a minimized state is not drawn (it is just black).

[Steps to reproduce]
1. Open a window
2. Minimize the window
3. Lock the screen
4. Unlock the screen
5. Restore the window

[What should happen]
* The window content should be drawn as expected.

[What happens]
* The window is not drawn. See attachment

[Workaround]
* Any window action will paint the window again, for example re-sizing, minimizing and restoring again, but not moving the window.
* Opening the unity dash or HUD also works.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: unity 7.1.2+14.04.20140313-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6
Uname: Linux 3.13.0-17-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] Is a directory: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 331.38 Wed Jan 8 19:32:30 PST 2014
 GCC version: gcc version 4.8.2 (Ubuntu 4.8.2-16ubuntu6)
.tmp.unity.support.test.0:

ApportVersion: 2.13.3-0ubuntu1
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Mon Mar 17 17:18:44 2014
DistUpgraded: 2014-03-14 11:39:48,168 DEBUG enabling apt cron job
DistroCodename: trusty
DistroVariant: ubuntu
DkmsStatus:
 bbswitch, 0.7, 3.11.0-18-generic, x86_64: installed
 bbswitch, 0.7, 3.13.0-17-generic, x86_64: installed
 nvidia-331-updates, 331.38, 3.13.0-17-generic, x86_64: installed
GraphicsCard:
 NVIDIA Corporation GF108GLM [Quadro 1000M] [10de:0dfa] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Hewlett-Packard Company Device [103c:1631]
InstallationDate: Installed on 2013-11-22 (115 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MachineType: Hewlett-Packard HP EliteBook 8560w
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-17-generic root=UUID=0668e908-5441-4ad5-ae8f-9eb19d0b27a6 ro quiet splash
SourcePackage: unity
UpgradeStatus: Upgraded to trusty on 2014-03-14 (3 days ago)
dmi.bios.date: 06/11/2012
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: 68SVD Ver. F.27
dmi.board.name: 1631
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 01.3B
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvr68SVDVer.F.27:bd06/11/2012:svnHewlett-Packard:pnHPEliteBook8560w:pvrA0001D02:rvnHewlett-Packard:rn1631:rvrKBCVersion01.3B:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP EliteBook 8560w
dmi.product.version: A0001D02
dmi.sys.vendor: Hewlett-Packard
version.compiz: compiz 1:0.9.11+14.04.20140310-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.52-1
version.libgl1-mesa-dri: libgl1-mesa-dri 10.1.0-1ubuntu1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 10.1.0-1ubuntu1
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.15.0-1ubuntu7
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.8.2-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.3.0-1ubuntu3
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.910-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.10-1ubuntu2
xserver.bootTime: Mon Mar 17 15:19:40 2014
xserver.configfile: default
xserver.errors: open /dev/fb0: No such file or directory
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:

xserver.version: 2:1.15.0-1ubuntu7

[Stephen M. Webb (bregma)]

Fix Released in Unity Unity 7.2.0.