Fix bug #345. The last hit for a file might have been before the last window, so we can't clear copies. To reduce the load, we only store real copy entries instead of storing hashes for every revision.

#!/bin/sh

hg init
mkfifo p

hg serve --stdio < p &
P=$!
(echo lock; echo addchangegroup; sleep 5) > p &
Q=$!
sleep 3
kill -HUP $P
wait
ls .hg