bug#3192: 23.0.92; disabling tooltip-mode inhibits showing Customize error msgs

[Eli Zaretskii]

> From: Mauro Aranda <maurooaranda@gmail.com>
> Date: Sun, 1 Sep 2019 07:43:42 -0300
> Cc: 3192@debbugs.gnu.org
> 
> +     ;; Only stop displaying the message when the current message is our own.
> +     ;; This has the advantage of not clearing the echo area when
> +     ;; running after an error message was displayed.  (Bug#3192)
> +     ((equal-including-properties tooltip-help-message (current-message))
>        (message nil)))))

I think this will effectively disable tooltip messages in the echo
area in too many situations.

How about if we show the tooltip in these cases for only some short
enough period of time, like 2 sec, and then restore the original
contents of the echo area?