Code review comment for lp:~andreas-pokorny/mir/rebase-fix-1550050

> We probably don't need this on trunk. Either we:
>
> 1. release 0.20.x from mir/0.20 - which already has this fix;
> 2. release a better solution (which I understand will break ABI) as 0.21; or,
> 3. we release 0.21 with this solution and apply the better solution in 0.22
>
> I think we intend to release 0.20.3 and don't need this (yet).

...we went for option 3