bug#21681: [PATCH] Fix formatting of lexical-binding at eof warning

[Eli Zaretskii <eliz@gnu.org>]

> Date: Wed, 14 Oct 2015 20:53:39 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 21681@debbugs.gnu.org
> 
> > Date: Wed, 14 Oct 2015 13:47:40 -0400
> > From: Noam Postavsky <npostavs@users.sourceforge.net>
> > Cc: 21681@debbugs.gnu.org
> > 
> > How about making display-warning print all TYPE symbols then?
> 
> Fine with me, but I don't know enough about display-warning and its
> uses to tell if this could cause some harm somewhere.  Maybe someone
> else will know; if you hear no objections in a few days, please go
> ahead.

Having now looked at the code, I actually don't understand why the
documentation says the symbol should be a custom group.  Nothing in
the code enforces that or relies on that, so it sounds like a
gratuitous limitation to me.  Names of custom group are usually so
general that they don't really add any useful information to the
message.