Remove the "X11 open display :0" work around.
Remove the "X11 open display :0" work around.

The tests now are run in a way that they can read the `$DISPLAY` env
variable and so this work around is not necessary any more. It was also
quite naive - i.e. my machine has the display on `:1` by default and
attempting to open `:0` causes build spam (in apic).

Qining/gapid,google/agi,pmuetschard/gapid,Qining/gapid,pmuetschard/gapid,google/agi,google/agi,pmuetschard/gapid,google/gapid,pmuetschard/gapid,google/gapid,google/gapid,google/agi,google/gapid,google/gapid,google/agi,Qining/gapid,pmuetschard/gapid,google/agi,google/agi,pmuetschard/gapid,Qining/gapid,google/agi,google/gapid,Qining/gapid,Qining/gapid,Qining/gapid,pmuetschard/gapid,google/gapid,google/gapid,Qining/gapid,pmuetschard/gapid