The property uses an array with the following CSS style syntax
[ top, right, bottom, left ] or
[ top, left/right, bottom ] or
[ top/bottom, left/right ] or
[ top/right/bottom/left ]
https://bugzilla.gnome.org/show_bug.cgi?id=676367
It's the conformance test suite: there's no need to namespace the files,
just like there's no need to namespace the units.
This commit does not change the Cogl tests: they will be moved to Cogl
over time, and it's easier to do if we leave them as they are.