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.
#header#
<title>Mercurial repositories index</title>
</head>
<body>
<h2>Mercurial Repositories</h2>
The specified repository "#repo|escape#" is unknown, sorry.
Please go back to the main repository list page.
#footer#