Removing a cookie from within a Chrome Extension

Question

I want to remove a Cookie (according to some criteria) from within a Chrome Extension. According to the documentation of chrome.cookies.remove it expects an object with the fields url (The URL associated with the cookie) and name (The name of the cookie to remove).

Now a cookie has the following fields: name, value, domain, hostOnly, path, secure, httpOnly, session, expirationDate, storeId but no url. How do I get the URL of a specific cookie so I can remove it?

For reference one of my cookies looks like this:

domain: ".google.com"
expirationDate: 1364393586
hostOnly: false
httpOnly: false
name: "PREF"
path: "/"
secure: false
session: false
storeId: "0"
value: "ID=8<snip>u"

Answer 1

After some trial and error here's how I get the URL, this seems to work for everything (except perhaps file://)

function extrapolateUrlFromCookie(cookie) {
    var prefix = cookie.secure ? "https://" : "http://";
    if (cookie.domain.charAt(0) == ".")
        prefix += "www";

    return prefix + cookie.domain + cookie.path;
}