largefiles: redo heads interception The largefiles extension replaces the "heads" wire command and tries to redirect all uses towards the custom "lheads" wire command. As seen in issue6384, this doesn't currently work for ssh. Instead of hooking into the _callstream interface, properly register the command for the peer instance and monkeypatch the executor to do the redirection. This works transparently for both all kinds of peers and both for the batch and non-batch case. Differential Revision: https://phab.mercurial-scm.org/D9663

nodemap: match comment to actual code REV_OFFSET constant is 2, not 10. Differential Revision: https://phab.mercurial-scm.org/D9688

clone: update to active bookmark, if set This cannot happen during a normal Mercurial clone, but is useful for extensions like hg-git where we know what to check out — the Git HEAD — but do not wish to track it later on using the `@` bookmark. Test Plan: I have not included an explicit test, as this is much more easily tested within the `hg-git` test suite. Differential Revision: https://phab.mercurial-scm.org/D9638

branchmap: micro-optimize branchinfo changelogrevision() is supposed to be used if not all data of changelog.read is used. This is the case here as only the extra field is used. This also improves extensibility as at least hgext.git doesn't implement changelog.read. Differential Revision: https://phab.mercurial-scm.org/D9626

contrib: py3 compat for perfnodemap Differential Revision: https://phab.mercurial-scm.org/D9687

comments: fix typos Differential Revision: https://phab.mercurial-scm.org/D9689