bug#39379: 27.0.60; Fix for #38457 broke ido-vertical-mode

[Eli Zaretskii]

> Cc: 39379@debbugs.gnu.org
> From: Jimmy Yuen Ho Wong <wyuenho@gmail.com>
> Date: Sun, 2 Feb 2020 13:58:36 +0000
> 
> 1. $ echo "(ido-mode)(require 'ido-vertical-mode)(ido-vertical-mode)" >
> .emacs
> 
> 2. $ emacs
> 
> 3. C-x C-f
> 
> 4. The Find file prompt is missing since that commit.

I see, thanks.

However, I'm not sure your proposal is the optimal solution: what will
happen if ido-exhibit uses the old code, and a message is displayed
while the user goes through the completion candidates?  The trick with
the overlay was to make sure the message is displayed without
overwriting the minibuffer prompt.