Make the combination of mod_proxy_ajp and mod_rewrite work correctly.

* modules/proxy/proxy_ajp.c

  (ap_proxy_ajp_request): Update call to ajp_send_header().


* modules/proxy/ajp.h

  (ajp_send_header): Add a uri parameter.


* modules/proxy/ajp_header.c

  (ajp_marshal_into_msgb): Add a uri parameter and use the
   passed in uri instead of r->uri.

  (ajp_send_header): Add a uri parameter.  Update call to
   ajp_marshal_into_msgb().


* modules/mappers/mod_rewrite.c

  (is_absolute_uri): Add handling of 'ajp' and 'balancer' schemes.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@124584 13f79535-47bb-0310-9956-ffa450edef68