tests/test-empty-dir.t

resolve: when resolve.mark-check=abort, downgrade to warning if pats specified

Previously, with --config resolve.mark-check=abort, running `hg resolve -m foo`
would abort and emit a message saying to use --all.  This command does not work,
though: `hg resolve -m foo --all`, and it's really weird for --all to be the
"--force" flag.

My original goal with the option was to make it so that `hg resolve -m` (no
filename arguments) was safer, which is why --all is used; in my mind, `hg
resolve -m foo` should always mark it as resolved, and `--all` is how you
specify "all the files", so that's why I chose `hg resolve -m --all` as the way
out of `hg resolve -m` aborting. This commit makes all of this work the way it
was meant to in my head :)

Differential Revision: https://phab.mercurial-scm.org/D5218

  $ hg init

  $ echo 123 > a
  $ hg add a
  $ hg commit -m "first" a

  $ mkdir sub
  $ echo 321 > sub/b
  $ hg add sub/b
  $ hg commit -m "second" sub/b

  $ cat sub/b
  321

  $ hg co 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ cat sub/b 2>/dev/null || echo "sub/b not present"
  sub/b not present

  $ test -d sub || echo "sub not present"
  sub not present