message: Allow "400 Bad Request" replies to test for invalid host names
  (Ubuntu 14.04's httpd responds like that)
diff: @@ -31,4 +31,4 @@ echo -e "GET /mod_pagespeed_example/ HTTP/1.1\nHost: 127.0.0.\xEF\xBF\xBD\n" >&3
  read -t 1 OUT <&3
  # Expect a 200 response and not, say, EOF.
  -check_from "$OUT" grep -q "HTTP/1.[01] 200 OK"
  +check_from "$OUT" grep -q "HTTP/1.[01] (200 OK|400 Bad Request)"
  