need help again - not bypassing filters when redirecting subrequests

[André Malo <nd...@perlig.de>]

The attached patch is - IMHO - ready for commit, but I'd very like some 
review from a subrequest/redirect/filter guru ;-).

PR 17629 deals with the problem, that internally redirected subrequests are 
not compressed (the main request has deflate in place). In particular they 
are meet the original filterchain too late (r->proto_output_filters) and 
thus skip the output_filters that are already in place.

There are some testcases, that work for me after applying the patch.
(standard installation)
- the testcase described in the PR (include virtual of a cgi script which 
  sends a Location header to a local file)
  [internal_redirect]

- <!--#include virtual="/" --> (mod_dir and type-map)
  [internal_fast_redirect and internal_redirect]

- <!--#include virtual="/manual/" --> (mod_dir and multiviews)
  [internal_fast_redirect and internal_fast_redirect]

- <!--#include virtual="/manual/index.html" --> (multiviews only)
  [internal_fast_redirect]

As said, please review. If nobody objects, I'm going to commit this fun 
these days.

TIA, nd
-- 
my @japh = (sub{q~Just~},sub{q~Another~},sub{q~Perl~},sub{q~Hacker~});
my $japh = q[sub japh { }]; print join       #########################
 [ $japh =~ /{(.)}/] -> [0] => map $_ -> ()  #            André Malo #
=> @japh;                                    # http://www.perlig.de/ #