localrepo: execute appropriate actions for dirstate at releasing transaction Before this patch, in-memory dirstate changes are still kept over a transaction scope boundary regardless of the result of it. For "all or nothing" policy of the transaction, in-memory dirstate changes should be: - written out at successful closing a transaction, because subsequent 'dirstate.invalidate()' can lose them - discarded at failure of a transaction, because outer 'wlock.release()' or so may write them out To discard all changes in a transaction completely, this patch also restores '.hg/dirstate' by '.hg/journal.dirstate' at failure, because 'transaction' itself does nothing for files related to '.hg/journal.*' in such case (therefore, renaming in this patch is safe enough). This is a part of preparations for "transactional dirstate". See also the wiki page below for detail about it. https://mercurial.selenic.com/wiki/DirstateTransactionPlan This patch also removes redundant 'dirstate.invalidate()' just before aborting a transaction for shelve/unshelve.