Restores a transaction.managed to fix Django 1.3 & 1.4

Author: BertrandBordage

johnny/tests/cache.py

@@ -328,6 +328,7 @@ def test_savepoints(self):
         self.assertEqual(ostart.title, g2.title)
         self.assertTrue(hit)
 
+        managed(False, 'default')
         transaction.leave_transaction_management("default")
         transaction.leave_transaction_management("second")