overlwayworkingctx: remove doubly bad reference to wrapped ctx for copies...
overlwayworkingctx: remove doubly bad reference to wrapped ctx for copies
`_wrappedctx` lives on overlwayworkingctx, not on the repo object, so
we should access it as `._wrappedctx`, not `._repo._wrappedctx`. More
importantly, the overlayworkingctx is relative to its base, not
including it, so the copies returned should not include copies made in
the base.
Differential Revision:
https://phab.mercurial-scm.org/D7801