[Mir] Unity8 crashes when an app tries to exit itself (unity8 crashed with SIGABRT in raise())

If an app have a 'quite' button i.e. the One that closes the app, tapping that while running Mir crashes Unity8 and one have to restart the phone to get back to a working state.

1. open system settings
2. go to Background panel
3. try to change the wallpaper so that content picker appear
4. tap 'Cancel'

What happens:
Unity crashes.

ProblemType: Crash
DistroRelease: Ubuntu 13.10
Package: unity8 7.81.3+13.10.20130927.3-0ubuntu1
Uname: Linux 3.4.0-3-mako armv7l
ApportVersion: 2.12.5-0ubuntu1
Architecture: armhf
CrashCounter: 1
Date: Fri Oct 4 11:51:41 2013
ExecutablePath: /usr/bin/unity8
InstallationDate: Installed on 2013-10-03 (0 days ago)
InstallationMedia: Ubuntu Saucy Salamander (development branch) - armhf (20131003.2)
MarkForUpload: True
ProcCmdline: unity8
Signal: 6
SourcePackage: unity8
StacktraceTop:
 ?? () from /lib/arm-linux-gnueabihf/libc.so.6
 raise () from /lib/arm-linux-gnueabihf/libc.so.6
 abort () from /lib/arm-linux-gnueabihf/libc.so.6
 __gnu_cxx::__verbose_terminate_handler() () from /usr/lib/arm-linux-gnueabihf/libstdc++.so.6
 ?? () from /usr/lib/arm-linux-gnueabihf/libstdc++.so.6
Title: unity8 crashed with SIGABRT in raise()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm autopilot cdrom dialout dip nopasswdlogin plugdev sudo tty video