jsxc: Bypass issue with stronghold to get the app working again

stronghold seems to have an issue with Django 2.1 decorators. A fix has not
been released yet.

Closes: #1697.

Tests:

- Functional tests for JSXC.

- Vist JSXC, login using FreedomBox account. Chat rooster becomes available.

- Log out, ensure that JSXC page is available.

- Log in, ensure that JSXC page is available.

Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/modules/jsxc/urls.py

@@ -19,10 +19,11 @@ URLs for the JSXC module
 """
 
 from django.conf.urls import url
+from stronghold.decorators import public
 
 from .views import JSXCAppView, JsxcView
 
 urlpatterns = [
     url(r'^apps/jsxc/$', JSXCAppView.as_view(), name='index'),
-    url(r'^apps/jsxc/jsxc/$', JsxcView.as_view(), name='jsxc')
+    url(r'^apps/jsxc/jsxc/$', public(JsxcView.as_view()), name='jsxc')
 ]

plinth/modules/jsxc/views.py

@@ -18,9 +18,7 @@
 Views for the JSXC module
 """
 
-from django.utils.decorators import method_decorator
 from django.views.generic import TemplateView
-from stronghold.decorators import public
 
 from plinth.modules import config, jsxc
 from plinth.views import AppView
@@ -41,11 +39,6 @@ class JsxcView(TemplateView):
     """A simple page to embed Javascript XMPP Client library."""
     template_name = 'jsxc_launch.html'
 
-    @method_decorator(public)
-    def dispatch(self, *args, **kwargs):
-        """Dispatch a get, post etc. request."""
-        return super().dispatch(*args, **kwargs)
-
     def get_context_data(self, *args, **kwargs):
         """Add domain information to view context."""
         context = super().get_context_data(*args, **kwargs)