match: resolve filesets against the passed `cwd`, not the current one
This allows filesets to be resolved relative to `repo.root`, the same as other
patterns are since
f02d3c0eed18. The current example in contrib/ wasn't working
from the tests directory because of this.
Differential Revision: https://phab.mercurial-scm.org/D7570
ERROR: FIXME: This is a known failure of filelog.size for data starting with \1\n
OK.