Add test for editing monolingual Xliff file

Issue #816
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/trans/tests/test_views.py

@@ -769,6 +769,13 @@ class EditXliffTest(EditTest):
         return self.create_xliff()
 
 
+class EditXliffMonoTest(EditTest):
+    has_plurals = False
+
+    def create_subproject(self):
+        return self.create_xliff_mono()
+
+
 class EditLinkTest(EditTest):
     def create_subproject(self):
         return self.create_link()