fix handling of multiple Content-type headers This can happen if an error happens while sending application/mercurial-0.1 content. The error page will be sent resulting (for at least lighttpd) in the following headers: Content-type: application/mercurial-0.1 Content-type: text/html which result in req.proto = 'application/mercurial-0.1, text/html' fix issue344

#!/bin/sh
# http://www.selenic.com/mercurial/bts/issue433

hg init a
cd a       
echo a > a 
hg commit -Ama 

hg parents -r 0 doesnotexist
true