narrow: move checking for narrow requirement into _narrowmatch() We want to move narrowmatch() and others into core, so we need to get rid of the dependence on the "narrow_opts" from the closure in narrowrepo.wraprepo(). We can simply check if the narrow requirement is set. I think that seems like an improvement regardless of moving narrowmatch(). Differential Revision: https://phab.mercurial-scm.org/D2489