bug#1899: url-cookie-retrieve is not prepared for missing localpart

[Klaus Straubinger]

In GNU Emacs 22.3.1 (i386-mingw-nt5.1.2600) of 2008-09-06 on SOFT-MJASON
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4)'


the function url-cookie-retrieve (defined in lisp/url/url-cookie.el) is
not prepared for the case that the parameter localpart could be nil:
(regexp-quote nil) is an error. This is especially problematic since
the corresponding function for setting cookies, url-cookie-store,
defines the parameter localpart as optional.

Test example:
(require 'url-cookie)
(url-cookie-store "test" "42" nil "www.gnu.org")
followed by
(url-cookie-retrieve "www.gnu.org" nil)

-- 
Klaus Straubinger