bug#69739: 30.0.50; `type-of` is not precise enough

[Eli Zaretskii]

> Cc: monnier@iro.umontreal.ca
> Date: Mon, 11 Mar 2024 19:19:40 -0400
> From:  Stefan Monnier via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> Still, any change as suggested here would be an incompatible change, so
> there's risk it'll break some code out there (`type-of` is not used very
> often, but it *is* used).  Another option is to introduce a new function
> which does the same as `type-of` but with changes like the ones above.
> (we could even decide to give it a `cl-generic-` prefix to discourage
> its use elsewhere so we can be more free to change its return value in
> the future).

I'd prefer a non-breaking change, if possible and reasonable.

Thanks.