copies: avoid calculating debug-only stuff without --debug...
copies: avoid calculating debug-only stuff without --debug
`renamedeleteset` and `divergeset` is only used with
`repo.ui.debugflag`, so let's avoid calculating them otherwise. While
at it, I also added a `del renamedeleteset` for consistency.
Differential Revision:
https://phab.mercurial-scm.org/D7976