workingctx: move setparents() logic from localrepo to mirror overlayworkingctx...
workingctx: move setparents() logic from localrepo to mirror overlayworkingctx
It would be nice to later be able to call `wctx.setparents()` whether
`wctx` is a `workingctx` or an `overlayworkingctx`.
Differential Revision:
https://phab.mercurial-scm.org/D7823