Update ir_model_fields.py

mass_editing/models/ir_model_fields.py

@@ -13,7 +13,7 @@ class IrModelFields(models.Model):
         model_domain = []
         for domain in args:
             if (len(domain) > 2 and domain[0] == 'model_id' and
-                    isinstance(domain[2], basestring)):
+                    isinstance(domain[2], basestring) and list(domain[2][1:-1])):
                 model_domain += [('model_id', 'in',
                                   map(int, domain[2][1:-1].split(',')))]
             else: