bug#23933: 25.1.50; Run a buffer-local hook with mapc

[Eli Zaretskii]

> From: Tino Calancha <tino.calancha@gmail.com>
> Date: Mon, 11 Jul 2016 02:31:52 +0900 (JST)
> cc: Stefan Monnier <monnier@iro.umontreal.ca>, tino.calancha@gmail.com, 
>     23933@debbugs.gnu.org, kifer@cs.stonybrook.edu, 
>     npostavs@users.sourceforge.net
> 
> > Tino, can you figure out why t is there?  Perhaps the solution is
> > simply to remove it?
> Just explained in previous e-mail by Noam.
> I have tried another approach: drop the let binding
> and call run-hooks over the actual hook, as follows:

Can't we simply remove the t?  If not, why not?