Bug#442907: xserver-xorg-video-mga: Multihead doesn't work on G450

[kls <debbts@eamp.org>]

With the update to libpixman, I can now run 1.9.99. It mostly works,
except 2d performance is abysmal -- full-screen windows (1152x900 for
me) take about a second to redraw. (however, 3d performance is as
good, or maybe slightly better, than it ever was)

Is this useful for me to report now, or should I wait for whenever it
gets pushed into unstable (when upstream will be more nearly finished)?
(If so, I've noticed that randr forgets the doublescan flag, and that
wmnet's window contents gets placed in the wrong place)

In any case, 1.4.7 is sufficiently broken (since dual-heading doesn't
work at all) that I'd like to recommend that it not be allowed to
propagate. 

Thank you!
 - robert jacobs