committablectx: simplify caching the status Previously, workingctx had custom variables for the unknown, ignored, and clean list of files of status. These then got moved to committablectx and, after the refactoring of localrepo.status, are no longer needed. We, therefore, simplify the whole mess. As a bonus, we are able to remove the need for having 'assert'.

localrepo: remove cache code now handled by _prestatus This patch removes the last of the 'working' variable that was sprinkled throughout localrepo.status which paves the way for future patches to use the object oriented design of contexts to handle calculating the status.

workingctx: add note about super._prestatus calling manifest

basectx: preserve loading the cached manifest in _prestatus This is just a copy from localrepo.status and is a small step to removing that method entirely. The prestatus hook is only called for changectx's, thereby ensuring that the same behavior is guaranteed.

localrepo: use new subrev method of context.py With the machinery in place, we use context.subrev instead of testing for a workingctx directly. This allows more flexibility for later patches that will add memctx to the mix.

committablectx: add subrev method to return None This allows a future patch to use object oriented style to remove an if statement in the status method.

basectx: add subrev method to return the rev of a subrepo given a subpath This will be used in an upcoming patch to simplify the status method by eliminating an if block.

merge with stable

bundle2: fix bundle2 pulling all revs on empty pulls When bundle2 was enabled, if hg pull had no commits to pull, it would print 'no changes found' and then download the entire repository from the server. This was caused by heads and common being set to None, which gets treated as heads=cl.heads() and common=[nullid], which means download the entire repo. Pulling bundles without a changegroup is a valid use case (like if we're just updating bookmarks), so this modifes the bundle code to allow not adding changegroups. This is backport of ab5040cd5749.

exchange: fix bad indentation Those two lines where double indented for no good reasons. This is backport of 71931b789424.