composite: Remove silly indirection around compRepaintBorder

If we need to repaint a window's border, then said window will certainly
still exist by the time we get around to ProcessWorkQueue. So there's no
reason to look it up by its XID, the WindowPtr itself is fine.

Signed-off-by: Adam Jackson <ajax@redhat.com>
1 job for compRepaintBorder in 2 minutes and 58 seconds (queued for 9 seconds)
latest
Status Job ID Name Coverage
  Test
failed #34805
job

00:02:58

 
Name Stage Failure
failed
job Test
 dmesg-warn:        0
dmesg-fail: 0
changes: 0
fixes: 0
regressions: 0
total: 475
time: 00:00:57
+ exit 1
ERROR: Job failed: exit code 1