gnome-shell freeze break request

[drago01 <drago01 gmail com>]

Hi,

I'd like to get the patch from
https://bugzilla.gnome.org/show_bug.cgi?id=696404 into 3.8 it fixes a
regression where
opening the application view in the overview (or any other shell UI
where we use the edge fade effect) can cause a
30 second lag for every paint on older hardware.

The patch from the bug just reverts the behavior to what we had in
3.6, so it is low (~0) risk. We can revisit for 3.10
once / if we have a fixed mesa but for now this is the best thing to do.