...freeze break request for at-spi2-atk

[Matthias Clasen <matthias clasen gmail com>]

...here is the fix for the problem with a freezing login screen that I
was alluding to earlier:

https://bugzilla.gnome.org/show_bug.cgi?id=658013

This fixes a workaround that Mike Gorse put into 3.1.92. I have tested
this on my machine, and where it would previously hang 100%, I got 10
successful logins in 10 attempts with this patch. Mike independently
came up with the same fix.