Remove compatibility code for unsupported django, wagtail versions

wagtailvideos/models.py

@@ -227,10 +227,7 @@ class AbstractVideo(CollectionMember, index.Indexed, models.Model):
 
     @classmethod
     def get_transcode_model(cls):
-        if django.VERSION >= (1, 9):
-            return cls.transcodes.rel.related_model
-        else:
-            return cls.transcodes.related.related_model
+        return cls.transcodes.rel.related_model
 
     def get_transcode(self, media_format):
         Transcode = self.get_transcode_model()

wagtailvideos/views/chooser.py

@@ -118,12 +118,7 @@ def chooser_upload(request):
             video.save()
 
             # Reindex the video to make sure all tags are indexed
-            from wagtail.wagtailcore import __version__
-            if __version__.startswith("1.4"):
-                for backend in get_search_backends():
-                    backend.add(video)
-            else:
-                search_index.insert_or_update_object(video)
+            search_index.insert_or_update_object(video)
 
             return render_modal_workflow(
                 request, None, 'wagtailvideos/chooser/video_chosen.js',