pagespeed/ngx_pagespeed — pull request #54 by jeffkaufman (2012-11-14 21:07:17+00:00)
Title: headers: content type

When setting content type you also need to set content_type_len and null out
content_type_lowcase or else downstream filters might look in the wrong place
for it.

See:
http://stackoverflow.com/questions/8427528/nginx-gzip
http://lxr.evanmiller.org/http/source/http/ngx_http_core_module.c#L1659