Possible fix for Bug 1548992.
This patch computes the display number in
initialize-x11-values instead of x-set-device-variables.
Not sure it's 100% correct, but it works for me.
Garnet doesn't know how to handle a display where the
display number is not 0. It loses the display number
when opening the display, and uses 0 instead of the
actual number.
This is easily reproduced by ssh'ing to another machine
with X11 forwarding. The display is usually
localhost:10.0 or so. Garnet doesn't use the 10 but
uses 0 instead.
