changegroup: pass clrevtolocalrev to each group clrevtolocalrev is a per-changegroup group mapping revisions to aid with shallow clone. Back when this functionality was implemented in an extension, this dict was added to the packer instance so monkeypatched functions could reference it there. Now that this code is part of core, we can pass the dict to each consumer properly so it doesn't have to live on the cgpacker instance. This commit does that. Differential Revision: https://phab.mercurial-scm.org/D4193

changegroup: combine _generatefiles() into generatefiles() These were split out in a06aab274aef as part of moving the narrow code into core. They don't need to be separate functions. Differential Revision: https://phab.mercurial-scm.org/D4192

changegroup: define linknodes callbacks in generatefiles() This is how it is done everywhere else. But the logic here is a bit more complex because shallow clone needs to reference the original linknode implementation. But at least now all function implementations are defined in the same place. Differential Revision: https://phab.mercurial-scm.org/D4191

changegroup: track changelog to manifest revision map explicitly Previously, self._nextclrevtolocalrev was only populated as part of the changelog lookup callback. But cgpacker._close() was looking at self._nextclrevtolocalrev on every invocation. Since self._nextclrevtolocalrev is for communicating the mapping of changelog revisions to manifest revisions, this commit refactors the code to make that explicit. The changelog state now stores this mapping. And after the changelog group is emitted, we update self._clrevtolocalrev with that dict. self._nextclrevtolocalrev is unused and has been deleted. Differential Revision: https://phab.mercurial-scm.org/D4190