rebase: don't rebase obsolete commit whose successor is already rebased This patch avoids unnecessary conflicts to resolve during rebase for the users of changeset evolution. This patch modifies rebase to skip obsolete commits if they are being rebased on their successors. It introduces a new rebase state 'revprecursor' for these revisions that are being skipped and a new message to inform the user of what is happening. This feature is gated behind the config flag experimental.rebaseskipobsolete When an obsolete commit is skipped, the output is: not rebasing 14:9ad579b4a5de "I", already in destination as 17:fc37a630c901 "K"