Compiz assertion error on successful authentication from locked session

[Luis Peregrina]

Steps to reproduce:

1. Lock the screen from a password protected user session.
2. Unlock the screen.

syslog contains the next entry:
compiz: pam_ecryptfs: seteuid error

Very low priority.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: compiz 1:0.9.12.2+16.04.20160823-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-109.132-generic 4.4.98
Uname: Linux 4.4.0-109-generic x86_64
NonfreeKernelModules: symap_custom_dkms_x86_64
.tmp.unity_support_test.0:

ApportVersion: 2.20.1-0ubuntu2.15
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: Fri Feb 2 14:40:11 2018
DistUpgraded: Fresh install
DistroCodename: xenial
DistroVariant: ubuntu
GraphicsCard:
 Intel Corporation Skylake Integrated Graphics [8086:191b] (rev 06) (prog-if 00 [VGA controller])
   Subsystem: Dell Skylake Integrated Graphics [1028:06e0]
GsettingsChanges:
 b'org.compiz.core' b'outputs' b"['1366x768+0+0']"
 b'org.compiz.core' b'hsize' b'2'
 b'org.compiz.core' b'active-plugins' b"['core', 'composite', 'opengl', 'put', 'mousepoll', 'compiztoolbox', 'move', 'copytex', 'snap', 'grid', 'wall', 'commands', 'place', 'vpswitch', 'regex', 'imgpng', 'unitymtgrabhandles', 'resize', 'session', 'animation', 'expo', 'fade', 'ezoom', 'scale', 'workarounds', 'unityshell']"
 b'org.compiz.core' b'vsize' b'2'
InstallationDate: Installed on 2016-11-17 (442 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
MachineType: Dell Inc. Precision 3510
PackageArchitecture: all
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-109-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
SourcePackage: compiz
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/22/2016
dmi.bios.vendor: Dell Inc.
dmi.bios.version: 1.11.4
dmi.board.name: 0XC72F
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvr1.11.4:bd12/22/2016:svnDellInc.:pnPrecision3510:pvr:rvnDellInc.:rn0XC72F:rvrA00:cvnDellInc.:ct9:cvr:
dmi.product.name: Precision 3510
dmi.sys.vendor: Dell Inc.
version.compiz: compiz 1:0.9.12.2+16.04.20160823-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.83-1~16.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 17.2.4-0ubuntu1~16.04.4
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 17.2.4-0ubuntu1~16.04.4
version.xserver-xorg-core: xserver-xorg-core 2:1.18.4-0ubuntu0.7
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.1-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1.2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2
xserver.bootTime: Fri Feb 2 08:19:12 2018
xserver.configfile: default
xserver.errors: RADEON(G0): [XvMC] Failed to initialize extension.
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:
 product id 1199
 vendor LGD
xserver.version: 2:1.18.4-0ubuntu0.7