bug#56407: 29.0.50; desktop.el shouldn't be saving/restoring eglot--managed-mode, which is not for interactive use

[Eli Zaretskii <eliz@gnu.org>]

> From: João Távora <joaotavora@gmail.com>
> Cc: 56407@debbugs.gnu.org,  terra@diku.dk
> Date: Tue, 05 Jul 2022 20:53:33 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> I confirmed this with a stack trace requested from the user and came up
> >> with this workaround in the user's config:
> >> 
> >>     (add-to-list 'desktop-minor-mode-handlers
> >>                  '(eglot--managed-mode . ignore))
> >> 
> >> This works, but we should come up with something better.
> >
> > But why is the above not good enough?  You could also use
> > desktop-minor-mode-table, which is a defcustom.
> 
> At first I thought it was a customization variable and that would make
> it user-specific overwritable etc.  But I see now that evidently it is
> not.  According to the docstring of d-m-m-handlers, eglot.el could just
> just contain the above invocation, indeed.
> 
> But that has the downside that eglot.el must require "desktop.el" which
> IMO opinion too strongly couples the two packages.

I see no reason to require: you just add a value to the list, that's
all.

> I think I like Lars's solution best.

I don't: it makes the information spread out and harder to find.