url-unhex-string
url-unhex-string is an autoloaded compiled Lisp function in `url-util.el
'.
(url-unhex-string STR &optional ALLOW-NEWLINES)
Remove %XX embedded spaces, etc in a URL.
If optional second argument ALLOW-NEWLINES is non-nil, then allow the
decoding of carriage returns and line feeds in the string, which is normally
forbidden in URL encoding.