Backport the fix to handling Connection: close.  The existing code
  was impossible to follow; the new code sets up p_conn->close correctly,
  and uses that evaluated value to inject the appropriate choice immediately
  before passing the request to the backend server.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/proxy-reqbody-2.0.x@230729 13f79535-47bb-0310-9956-ffa450edef68