[patch] small refactor of the response middleware invocation
|Reported by:||Owned by:||nobody|
|Severity:||normal||Keywords:||handlers response middleware|
|Cc:||Triage Stage:||Design decision needed|
|Has patch:||yes||Needs documentation:||no|
|Needs tests:||no||Patch needs improvement:||no|
Factored the common code which invokes the response middleware out from WSGIHandler and ModPythonHandler and put it into BaseHandler.