Fixed SIGSEGV problem when a DirectoryIndex file is also the source

of an external redirection.  The problem was that the redirection would be
seen as a subrequest, but the redirection header fields were not being
promoted to the main response.

Submitted by: Roy Fielding and Paul Sutton
Reviewed by: Dean Gaudet, Randy Terbush, Jim Jagielski


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@77926 13f79535-47bb-0310-9956-ffa450edef68