I think this works about as well as it's going to. There may be a theoretical
issue that GDI draws to the window should end up in the backbuffer after a
flip, but I don't think we have tests showing that to actually be the case,
and generally speaking I'm not all that worried about it.
Signed-off-by: Henri Verbeet <hverbeet@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>