Upstream regions fix, claims to solve linuxmint/Cinnamon#698

This set of patches is claimed to solve linuxmint/Cinnamon#698, see https://github.com/linuxmint/Cinnamon/issues/698#issuecomment-18414455.

I have packaged the patch supplied by wisheu on top of the original upstream patches, for proper attribution.

As far as I can tell, from my limited testing, this seems to solve the issue on my setup (laptop + external monitor, NVidia graphics, nouveau driver).