bug#1305: [External] : bug#1305: All code that currently beeps should use visual bell instead

[Drew Adams]

> > I'm personally fine with that, but I suspect it would be controversial
> > as it would leave us with no way of beeping (visual or otherwise).
> 
> You get a message in the echo area...
> 
> As somebody else noted earlier, if you have visible-bell on, but use
> "-nw", that's the only notification you get -- there's no visible bell
> on the console.  So you could say that there's some precedence for using
> just the echo area as the only notification mechanism (beyond apparently
> all the popular Emacs distributions doing exactly that).

`echo-bell'...