Martin von Zweigbergk <martinvonz@google.com> [Fri, 11 Oct 2019 00:18:34 -0700] rev 43249
widening: pass in matchers instead of patterns
This matches how it's done for the non-ellipsis case. The oldmatch is
not used yet, but it should be used eventually when widening no longer
resends manifests and files the client already has.
Differential Revision: https://phab.mercurial-scm.org/D7099