Correctly use request's origin when determining same origin requests

[KiChjang]

In #17521, under the http_redirect_fetch step 7, we are still using the request's current URL's origin when making a comparison with the location URL's origin. This is incorrect, but when using the following (correct) code of comparing the origins:

let same_origin = match request.origin {
    Origin::Origin(ref origin) => *origin == location_url.origin,
    Origin::Client => false,
};

we encountered some WPT failures due to the code having an origin that is not what the WPT expects.