[mod_python] Change request: "allow req.args = None"

[Ron Gomes]

We use mod_python to rewrite URLs internally based on request criteria. 
As part of our processing, in our request handler we grab and then 
remove any request query parameters by setting

req.args = None

so that they will be invisible to later phases.

A change was necessary to src/requestobject.c in order to make this work 
since, as delivered, that line causes an exception to be thrown because 
the code only allows Python strings to be assigned to req.args.

===========================================

$ diff -c src/requestobject.c.ORIG src/requestobject.c
*** src/requestobject.c.ORIG	2013-11-11 22:21:34.000000000 -0500
--- src/requestobject.c	2014-02-18 15:36:14.401921415 -0500
***************
*** 1967,1972 ****
--- 1967,1977 ----
           return 0;
       }
       else if (strcmp(name, "args") == 0) {
+         if (val == Py_None) {
+             self->request_rec->args = 0;
+             return 0;
+         }
+
           MP_ANYSTR_AS_STR(v, val, 1);
           if (!v) {
               Py_DECREF(val); /* MP_ANYSTR_AS_STR */

===========================================

Assigning an empty string would work but the semantics of that are 
slightly different and are indistinguishable from an explictly-empty 
query string.

Can this be incorporated into mod_python, so that we don't have to 
retrofit this change into every new version?