* Restore the original request headers if the cached resource was stale, as they

  may be needed by further output filters like the byterange filter to make the
  correct decisions.

PR: 44579


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@636386 13f79535-47bb-0310-9956-ffa450edef68