revlog.py: always return tuples from parents and parentrevs There's at least one place doing parentrevs(rev) != (rev-1, -1), which is always true with revlog v0, since parentrevs returns a list in this case.

# should print nothing
# should print ? b/x
? b/x
# should print A b/x
A b/x
# should forget b/x
forgetting b/x
# should print nothing