Tracked down by Justin Erenkrantz.

* modules/cache/mod_disk_cache.c

  (store_headers): Stop second guessing mod_cache and just store the
   headers in a new file (overwriting the old).

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@156306 13f79535-47bb-0310-9956-ffa450edef68