py3: byteify the opener option to use `rust.index` to allow Rust revlogs...
py3: byteify the opener option to use `rust.index` to allow Rust revlogs
It looks like this corresponds to the byteified key written in localrepo in
8042856c90b6.
Differential Revision:
https://phab.mercurial-scm.org/D7818