Revert last fix; subset of last fix recommitted.

* url-auth.el (url-digest-auth): If the 'opaque' argument is not
being used, don't add it to the response text.

lisp/url/ChangeLog

 2008-02-25  John Wiegley  <johnw@newartisans.com>
 
-	* url-auth.el (url-digest-auth): Don't show prompt if
-	authentication succeeded on the previous pass.  Don't pass
-	"opaque" value if none is presented by the server.
+	* url-auth.el (url-digest-auth): If the 'opaque' argument is not
+	being used, don't add it to the response text.
 
 2008-01-21  Stefan Monnier  <monnier@iro.umontreal.ca>