ddraw/visual tests

[Paul Vriens]

Hi Stefan,

As you wrote most of the tests:

I'm looking into some of the ddraw:visual failures (windows 2000 and I guess 
only VMware).

Several tests draw quads but only if _BeginScene succeeded. Is it useful at all 
to check the colors afterwards if the quads are not drawn in the first place?

I don't want to mark all those failures as broken() if failing _BeginScene could 
just do with a win_skip() for the test of a particular test.