In 2.1.0, when a client tries to connect with an invalid namespace, an error was emitted: `Invalid namespace`. In 2.1.1, this error isn't emitted anymore. The only proper code diff between 2.1.0 and 2.1.1 seems to be [`local` added to `flags`](https://github.com/socketio/socket.io/compare/2.1.0...2.1.1#diff-9b2f90c89d460ee80ced18e01748824e). Any idea how could this simple change have such an impact?