bug#20744: shell-quote-argument in Emacs 24.5 and Emacs 25 on Windows cannot figure out path correctly

[Glenn Morris]

Eli Zaretskii wrote:

> Anyway, if we think ':' doesn't need to be quoted, how about removing
> it from the Posix branch of shell-quote-argument?

The comment there says "This should be safe enough even for really weird
shells." That's a much broader question than just Bash! :)

But I thought of an example that affects Bash:

scp localfile remotehost:

If "localfile" contains ":", things will get confused.
So it's probably best to leave it as-is.