bug#66979: Wrong number of arguments with completion-at-point

[Stefan Monnier via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

>> Some recent change broke completion-at-point:
>>
>> 0. emacs -Q
>> 1. (setq debug-on-error t)
>> 2. Type in the *scratch*:
>>
>>   (defun a M-C-i
>>
>> raises the error (wrong-number-of-arguments (2 . 2) 1)
>
> Stefan, this looks like another case for the recently fixed
> bug#58148, bug#58396, bug#58557.

So you're suggesting we should remove the `debug` from the
`condition-case` in `elisp--local-variables`?

This was added by Alan in:

    commit f931cebce76d911dfc61274e0a8c1de3627b9179
    Author: Alan Mackenzie <acm@muc.de>
    Date:   Wed Sep 20 15:51:17 2023 +0000

    Insert symbol `debug' into two condition-case handlers
    
    This fixes bug#65622.  Also correct a mismatch between a
    function to which advice is added, and that from which it is
    removed.
    
    * lisp/emacs-lisp/macroexp.el (internal-macroexpand-for-load):
    Add a `debug' to the condition-case handler for `error', so
    that a useful backtrace will be produced on a macro expansion
    error.
    
    * lisp/progmodes/elisp-mode.el (elisp--local-variables): Add
    `debug' to a condition-case handler, as above.  In the
    advice-remove call, give the same function, macroexpand-1, as
    in the corresponding advice-add call.

Alan do you remember why you also added the `debug` to the
condition-case in `elisp--local-variables`?
The rest of the commit looks right to me.

Macro expansion errors in there are perfectly normal since
`elisp--local-variables` routinely passes incomplete code to
macroexpand.  IOW most errors signal'd in there probably don't need to
be debugged at all.


        Stefan