upgrade: explicitly warn when a `--no-xxx` flag is overwritten
Some format upgrade/downgrades -needs- revlog to be recomputed. So we now
detect that individually and warn when it contradict explicitly passed flag.
This is part of a larger series to make `debugupgraderepo` smarter about which
revlog it picks by default.
Differential Revision: https://phab.mercurial-scm.org/D11869
#require execbit
$ hg init repo
$ cd repo
$ echo foo > foo
$ chmod 644 foo
$ hg ci -qAm '644'
$ chmod 755 foo
$ hg ci -qAm '755'
reverting to rev 0
$ hg revert -a -r 0
reverting foo
$ hg st
M foo
$ hg diff --git
diff --git a/foo b/foo
old mode 100755
new mode 100644
$ cd ..