Fix breakage in mod_mem_cache caused by the EnableSendFile patch. Specifically,

we need to save the file open flags from the file opened by the default handler.
Retrive those flags when building the apr_file_t on a cache hit.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@97265 13f79535-47bb-0310-9956-ffa450edef68