localrepo: reverse contexts in status This is a slight tweak to how localrepo.status calculates what files have changed. By forcing a changectx to be first operator and anything not a changectx to be the second operator, we can later exploit this to allow refactoring the status operation as a method of a context object. Furthermore, this change will speed up 'hg diff --reverse' when used with the working directory because the code will now hit a fast path without needing to calculate an unneeded second manifest.