plugin room_game, radiocol: RoomGame.send returns a Deferred.

src/test/test_plugin_misc_radiocol.py

@@ -30,6 +30,7 @@ from constants import Const
 from twisted.words.protocols.jabber.jid import JID
 from twisted.words.xish import domish
 from twisted.internet import reactor
+from twisted.internet import defer
 from twisted.python.failure import Failure
 
 from mutagen.oggvorbis import OggVorbis
@@ -381,6 +382,8 @@ class RadiocolTest(helpers.SatTestCase):
         for filename in self.playlist:
             self.plugin.deleteFile('/tmp/' + filename)
 
+        return defer.succeed(None)
+
     def tearDown(self, *args, **kwargs):
         """Clean the reactor"""
         helpers.SatTestCase.tearDown(self, *args, **kwargs)