bug#42422: fix: url-https-proxy-connect - CONNECT with Proxy-Authorization header

[Satoshi Nakagawa]

commit 27b37d16418cd64321505e721b40b6b5d730ebdf (HEAD -> 
fix/url-https-proxy-connect, fork/fix/url-https-proxy-connect)
Author: Satoshi Nakagawa <ghnacker@gmail.com>
Date:   Sun Jul 19 10:05:27 2020 +0900

    fix: url-https-proxy-connect - CONNECT with Proxy-Authorization header

diff --git a/lisp/url/url-http.el b/lisp/url/url-http.el
index 669c24571f..9c1219d5c0 100644
--- a/lisp/url/url-http.el
+++ b/lisp/url/url-http.el
@@ -1406,6 +1406,10 @@ The return value of this function is the retrieval 
buffer."
   (setq url-http-after-change-function 'url-https-proxy-after-change-function)
   (process-send-string connection (format (concat "CONNECT %s:%d HTTP/1.1\r\n"
                                                   "Host: %s\r\n"
+                                                  (let ((proxy-auth (let 
((url-basic-auth-storage
+                                                                           
'url-http-proxy-basic-auth-storage))
+                                                                      
(url-get-authentication url-http-proxy nil 'any nil))))
+                                                    (if proxy-auth (concat 
"Proxy-Authorization: " proxy-auth "\r\n")))
                                                   "\r\n")
                                           (url-host url-current-object)
                                           (or (url-port url-current-object)