Fix serious X server crash (xinerama + any QT app)

[Linus Arver]

Hello X developers,

I am writing this message to point your attention to a serious bug that
has been in X server since the 1.9 release, where starting _any_ QT app
(and some tcl/tk ones like fontforge) would _immediately_ crash the
entire X server, but only if Xinerama was enabled. I myself experienced
this bug on my dual monitors. Fortunately, I have already posted a
patch, but it seems an email/mailing list hiccup (my fault with Gmail)
placed it in the wrong thread.

Patch: http://lists.x.org/archives/xorg-devel/2010-October/014150.html

Actual thread: http://lists.x.org/archives/xorg-devel/2010-October/014149.html

Please merge this patch into the next release xserver release. It is
only a 1-liner change that fixes a 1-liner typo.

This patch has already been tested and used successfully by end-users at
Arch Linux, Ubuntu, Gentoo, etc.

Bug report: https://bugs.freedesktop.org/show_bug.cgi?id=30943

Further discussions:
https://bbs.archlinux.org/viewtopic.php?id=106125
https://bugs.launchpad.net/ubuntu/+source/qt4-x11/+bug/650539
http://bugs.gentoo.org/show_bug.cgi?id=339135

-Linus