These tests are broken.  You're setting the user agent then overwriting the request.

Note you can send all the options to the factory:
```python
    def test_does_not_redirect_a_whitelisted_urls(self):
        request = self.factory.get(
            path=settings.WHITELISTED_URL_PATHS[0] + '/app.js',
            HTTP_USER_AGENT=self.IE8)
        response = self.cbmw.process_response(request, self.response)
        self.assertEqual(self.response, response)
```

And you'll find a bug in your test config.