[cairo] A hack upon a pattern hack.

[Chris Wilson]

Hi all,
	can some of you take a few moments and glance over this change to
improve the REFLECT surface pattern hack.

The motivation for this was to workaround a bug in the directfb backend,
but whilst fiddling I took the time to address one of the TODO items and
to remove a detrimental special-casing for image destinations. Although
it passes the test-suite, the change is a little too intrusive with
quite a few side-effects that I felt uncomfortable pushing to 1.8. The
other aspect is that the REFLECT hack should die in 1.9 so it may be a
little premature to start modifying the code.

So please, have a look through and suggest test cases under which it
would break. (Patches to the test suite welcome ;-)
-- 
Chris