bookmarks: Avoid unconditional forwarding of bookmarks for the null revision
This patch fixes the following minor problem:
% hg bookmark -r null test
% hg bookmarks
test -1:000000000000
[...]
% hg commit
% hg bookmarks
* test 17:861ce7a241f9
That is: Bookmarks referring to the null revision are always forwarded
to the current revision.
echo % setting up repo
hg init test
cd test
echo a > a
hg ci -Ama
hg rm a
hg ci -mdel
echo % set up hgweb
hg serve -n test -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
cat hg.pid >> $DAEMON_PIDS
echo % revision
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/rev/tip'
echo % diff removed file
"$TESTDIR/get-with-headers.py" localhost:$HGPORT '/diff/tip/a'