topicidx: stop assigning index number to obsolete changesets
Obsolete changeset are no longer part of the stack, the old logic tried to
assigns them the index of their successors but this is flacky and error prone.
So we stop doing so.
This software was downloaded from
https://www.mercurial-scm.org/repo/evolve/
Copyright 2011 Peter Arrenbrecht <peter.arrenbrecht@gmail.com>
Logilab SA <contact@logilab.fr>
Pierre-Yves David <pierre-yves.david@ens-lyon.org>
Patrick Mezard <patrick@mezard.eu>
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On Debian systems, the complete text of the GNU General Public License version
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