dirstate: eliminate reference cycle from normalize
Bound methods hold a reference to self, so assigning a bound method to
an instance unavoidably creates a cycle. Work around this by choosing
a normalize method at walk time instead. Eliminate default arg while
we're at it.
#!/bin/sh
"$TESTDIR/hghave" fifo || exit 80
hg init
mkfifo p
hg serve --stdio < p &
P=$!
(echo lock; echo addchangegroup; sleep 5) > p &
Q=$!
sleep 3
kill -HUP $P
wait
echo .hg/* .hg/store/*