Fixed #20399: Setting userinfo to FALSE not transparent

Setting userinfo to FALSE in Net_URL2::setUserinfo() was not consistent
with getting it later on via Net_URL2::getUserinfo() as it was silently
converted to a zero-length string.

This has been fixed by not converting FALSE to string.

Author: ktomk

Net/URL2.php

@@ -271,7 +271,12 @@ public function setUserinfo($userinfo, $password = false)
         if ($password !== false) {
             $userinfo .= ':' . $password;
         }
-        $this->_userinfo = $this->_encodeData($userinfo);
+
+        if ($userinfo !== false) {
+            $userinfo = $this->_encodeData($userinfo);
+        }
+
+        $this->_userinfo = $userinfo;
         return $this;
     }