test helper: Ensure to populate JS_CATALOG in context

_script_i18n.html which tries to access 'jsi18n' url assumes
context['JS_CATALOG'] is populated, but openstack_dashboard test
helper clears it by mocking a context processor.
This leads to a error in rendering templates in unit tests.
Note that template rendering error is caught by a rendering engine
so unit test itself succeeds even when this happens.

Change-Id: I0f5013c4e9ed7b166c527b1aacd0302413948d51
Closes-Bug: #1699509

openstack_dashboard/context_processors.py

@@ -96,6 +96,12 @@ def openstack(request):
         context['x_trace_info'] = profiler.update_trace_headers(
             hmac_keys, parent_id=index_view_id)
 
+    context['JS_CATALOG'] = get_js_catalog(conf)
+
+    return context
+
+
+def get_js_catalog(conf):
     # Search for external plugins and append to javascript message catalog
     # internal plugins are under the openstack_dashboard domain
     # so we exclude them from the js_catalog
@@ -103,6 +109,4 @@ def openstack(request):
     regex = re.compile(r'^openstack_dashboard')
     all_plugins = conf.HORIZON_CONFIG['plugins']
     js_catalog.extend(p for p in all_plugins if not regex.search(p))
-    context['JS_CATALOG'] = '+'.join(js_catalog)
-
-    return context
+    return '+'.join(js_catalog)

openstack_dashboard/test/helpers.py

@@ -195,7 +195,10 @@ class TestCase(horizon_helpers.TestCase):
     def _setup_test_data(self):
         super(TestCase, self)._setup_test_data()
         test_utils.load_test_data(self)
-        self.context = {'authorized_tenants': self.tenants.list()}
+        self.context = {
+            'authorized_tenants': self.tenants.list(),
+            'JS_CATALOG': context_processors.get_js_catalog(settings),
+        }
 
     def _setup_factory(self):
         # For some magical reason we need a copy of this here.