Blender Git Loki

Fix ATI part of T45708, crash when enabling opensubdiv.

In fact exit was getting called because we
had an error in shader compilation:

Uniform buffer objects are in fact required.

Since it looks like original intent was to
write the shader against older GLSL version,
I will be adding an extension here instead
of a version.

Thanks to Anshu Arya for letting me borrow his machine through
VPN to do the debugging :)