Freeze break request: gnome-shell

[Marina Zhurakhinskaya <marinaz redhat com>]

Hi!

I'd like to land the fix here:
https://bugzilla.gnome.org/show_bug.cgi?id=659862

It ensures that we unset the clicked summary item in the message tray correctly and fixes a problem of an empty summary box pointer seen in the following screenshot staying behind when a notification associated with a tray icon is clicked.
http://mclasen.fedorapeople.org/gray-alien.png
 
Thanks,
Marina