Upstream: fixed changing method on X-Accel-Redirect.
Upstream: fixed changing method on X-Accel-Redirect.

Previously, only r->method was changed, resulting in handling of a request
as GET within nginx itself, but not in requests to proxied servers.

See http://mailman.nginx.org/pipermail/nginx/2015-December/049518.html.

firebase/nginx,firebase/nginx,firebase/nginx,firebase/nginx