tests: add a test showing grabbing of secret changeset turn it into draft
This patch adds a test showing wrong behavior of `hg grab` command which looses
the secret phase while grabbing a secret changeset.
evolve: add evolve info to cmdutil.afterresolvedstates
Adding evolve info to cmdutil.afterresolvedstate will improve the ui when we run
into merge conflicts while evolving. Once we resolve all the conflicts using `hg
resolve`, this will show a message saying "continue: hg evolve --continue".
Other extensions like rebase and shelve also use it and it's very helpful.