copies: always respect matcher arg to _forwardcopies() The function would ignore the matcher if the dirstate copies were requested. It doesn't matter in practice because all callers used the returned map only for looking up specific files from and those files had already been filtered by the matcher (AFACT). Still, it's a little confusing, so let's make it clearer by respecting the matcher in this case too. Differential Revision: https://phab.mercurial-scm.org/D1695