largefiles: backout f72d73937853 - linear updates handle m -> a differently f72d73937853 introduced a significant performance regression: All largefiles were marked 'normallookup' by linear (or noop) updates and had to be rehashed by the next command. The previous change introduced a different solution to the problem f72d73937853 solved and we can thus back it out again.

largefiles: mark lfile as added in lfdirstate when the standin is added This is an alternative solution to the problem addressed by f72d73937853. This implementation has the advantage that it doesn't mark clean largefiles as normallookup. We can thus avoid repeated rehashing of all largefiles when f72d73937853 is backed out. This implementation use the existing 'lfmr' actions that 23fe278bde43 introduced for handling another part of the same cases.

tests: add test coverage for lfdirstate invalidation of linear update f72d73937853 introduced a significant performance regression: All largefiles are marked 'normallookup' in lfdirstate by linear (or noop) updates and has to be rehashed by the next command. To avoid such regressions, keep an eye on the dirstate content after a plain 'hg up'.

test-subrepo-git: ignore global git config This was causing a test failure for people with company-wide settings. Still need a way to ignore local config.

tests/autodiff.py: explicitly only honor feature diffopts This test extension manages the opts it cares about on its own anyway.

cmdutil.changeset_printer: explicitly honor all diffopts This is used in hg log -p so the output is expected to be the same as that of hg diff.