phabricator: pass old `fctx` to `addoldbinary()` instead of inferring it Currently, removed binaries aren't marked as binaries on the left side, which sends the raw file view to a bad URL in the web interface. (See D8009) In order to handle marking the file as binary in the removed case, both contexts need to be provided by the caller, since there is no current fctx in the removed case. Having an explicit old fctx will also be useful to support a `--no-stack` option that rolls up the commit stack into a single review. The bug isn't fixed with this change- there's a missing call to it in `addremoved()` as well. But instead of spamming the list with a bunch of test diffs, all of the missing binary issues will be fixed at once later. Differential Revision: https://phab.mercurial-scm.org/D8218