title: Django Viewflow - flow.If with custom views doesn't work for me
body: <p>I have a flow like this:</p>
  
  <pre><code>    review_request = (
          flow.View(
              ReviewRequest,
          ).Permission(
              auto_create=True
          ).Next(this.check_response)
      )
  
  
      check_response = flow.If(cond=lambda act: True
          ).Then(
              this.approved_access_request
          ).Else(
              this.refused_access_request
          )
  
  
      approved_access_request = flow.View(
          AccessApproved,
      ).Assign(
          this.review_request.owner
      ).Permission(
          auto_create=True
      ).Next(this.end)
  
      refused_access_request = flow.View(
          AccessRefused,
      ).Assign(
          this.review_request.owner
      ).Permission(
          auto_create=True
      ).Next(this.end)
  </code></pre>
  
  <p>And a view:</p>
  
  <pre><code>class ReviewRequest(FlowMixin, generic.UpdateView):
      template_name = 'web/review-access-request.html'
      model = AccessRequest
  
      form_class = ReviewAccessRequestForm
  
      def get_object(self):
          return self.activation.process
  
      def request_details(self):
          return self.activation.process.access_request
  
      def form_valid(self, form):
          form.save()
          self.activation_done()
          next_view_url = self.get_success_url()
          return redirect(next_view_url)
  </code></pre>
  
  <p>The problem is the pages for AccessApproved and AccessRefused do not show. The assignment part works (shown by the admin material frontend), but the views are not executed. Instead there is a few second pause and the browser is send to the admin Inbox.</p>