bug#60960: 30.0.50; Keybinding for Info-search-next in info-mode

[Drew Adams <drew.adams@oracle.com>]

> AFAICS there is no keybinding for function Info-search-next in
> info-mode. This is the suggestion to add a respective binding.
> BTW I use the binding (define-key Info-mode-map (kbd "a")
> #'Info-search-next).

FWIW, in `info+.el' I bind `a' to `info-apropos'.

> Without this setting one could achive the same effect by pressing key "s"
> followed by RET which I find tiring compared to pressing just one key.

Any user can of course bind `Info-search-next'
to a key.

But I wonder how many users even use `s' these
days - as opposed to `C-M-s'.  Is there a
particular use case for it?  I may have just
forgotten that.

I can see how it might be convenient to have
different regexps remembered for `s' and `C-M-s',
so I guess that's one use case for having and
using both commands.  (And in that case, sure,
maybe bind `*-next*' - that definitely would
improve the use of `s'.)

That's possible because there are separate
histories, `Info-search-history' and
`regexp-search-ring'.

On the other hand, it might be good to have an
option that lets `Info-search' add its regexp
to `regexp-search-ring'.  Or vice versa: let
`Info-search' retrieve values from
`regexp-search-ring'.  Or both possibilities.

One way or another, there's some "overlap"
between isearching with `C-M-s' and the
nonincremental searching of `Info-search'.
And some room maybe for leveraging that - the
fact that there are two regexp histories and
two ways to search (incremental or not).

(BTW - seems like `Info-search' would be better
named `Info-regexp-search' or, following
`nonincremental-re-search-forward', something
like `Info-nonincremental-regexp-search'.)