Given an http.Response, get the resolved Location

[mccoyst]

It's supposed to be a full URL, but in practice people send (and thus browsers deal
with) relative URLs in "Location". Perhaps just a new method on *http.Response
that consults r.Header and r.Request to get the resolved Location URL, if present.

Bug requested by Brad Fitzpatrick.

[rsc]

Comment 1:

Owner changed to @bradfitz.

Status changed to Accepted.

[bradfitz]

Comment 2:

http://golang.org/cl/5117041

[bradfitz]

Comment 3:

This issue was closed by revision cf6d017.

Status changed to Fixed.