Comment 9 for bug 1281728

Ok... Seems I can reproduce it:

* Open an app
* swipe it away
* open the media player
* It will display a message that no file has been selected. click ok
=> the media player crashes and the previously opened app will show up.
* swipe the app away
=> *boom*

This seems to happen because unity-mir requests a new screenshot for the crashed app.

The crashing thread:

#0 0xb44496c0 in std::thread::_Impl<std::_Bind_simple<std::reference_wrapper<mir::scene::SnapshottingFunctor> ()> >::_M_run() () from /usr/lib/arm-linux-gnueabihf/libmirserver.so.15
#1 0xb6704a24 in ?? () from /usr/lib/arm-linux-gnueabihf/libstdc++.so.6

Which seems to be triggered by:

#0 0xb6140726 in __libc_do_syscall () from /lib/arm-linux-gnueabihf/libpthread.so.0
#1 0xb613b660 in __pthread_mutex_unlock_usercnt () from /lib/arm-linux-gnueabihf/libpthread.so.0
#2 0xb4448d0c in mir::scene::ThreadedSnapshotStrategy::take_snapshot_of(std::shared_ptr<mir::shell::SurfaceBufferAccess> const&, std::function<void (mir::shell::Snapshot const&)> const&) ()
   from /usr/lib/arm-linux-gnueabihf/libmirserver.so.15
#3 0xb4437fc2 in mir::scene::ApplicationSession::take_snapshot(std::function<void (mir::shell::Snapshot const&)> const&) () from /usr/lib/arm-linux-gnueabihf/libmirserver.so.15
#4 0xa77f33b4 in Application::updateScreenshot() () from /usr/lib/arm-linux-gnueabihf/qt5/imports/Unity-Mir/Unity/Application/libunityapplicationplugin.so
#5 0xa77f0800 in ApplicationManager::updateScreenshot(QString const&) () from /usr/lib/arm-linux-gnueabihf/qt5/imports/Unity-Mir/Unity/Application/libunityapplicationplugin.so
#6 0xa77ff5f0 in ?? () from /usr/lib/arm-linux-gnueabihf/qt5/imports/Unity-Mir/Unity/Application/libunityapplicationplugin.so