primitivus (chat): fixed filters clearing when changing filter while one already exists

frontends/src/primitivus/chat.py

@@ -276,12 +276,11 @@ class Chat(PrimitivusWidget, quick_chat.QuickChat):
             empty list to clear all filters
             only lang=XX is handled for now
         """
+        del self.filters[:]
         if args:
             if args[0].startswith("lang="):
                 lang = args[0][5:].strip()
                 self.filters.append(lambda mess_data: lang in mess_data.message)
-        else:
-            del self.filters[:]
 
         del self.mess_walker[:]
         for message in self.messages.itervalues():