Strange sizing problems with GridLayout [update]

[Thomas Schüßler <vindolin gmail com>]

I guess I ran into this bug: 
https://bugzilla.gnome.org/show_bug.cgi?id=725722
I was using ubuntu 14.04 beta with the default clutter 1.16.4 package.
Now I've build 1.18.2 from sources into a chroot env and now the grid 
layout looks like it should :)
We are targeting a custom embedded system and have to build everything 
by hand anyway so that's ok.

thanks

Thomas