message: Moving off method from LocalDocumentDeltaConnection.create() and adding connected property expected on socket
  Required for PR
  It needs connected property. I can't patch getter property similar to how we patch "off" method, so I have to change it, and given I'm changing it, remove patching part of "off" method as well
diff: @@ -13,6 +13,11 @@ export class LocalWebSocket implements core.IWebSocket {
  private readonly rooms = new Set<string>();
  private readonly subscriber: ISubscriber;
  + private _connected = true;
  + public get connected() {
  + return this._connected;
  + }
  +
  constructor(public readonly id: string, private readonly server: LocalWebSocketServer) {
  this.subscriber = new WebSocketSubscriber(this);
  }
  @@ -43,10 +48,19 @@ export class LocalWebSocket implements core.IWebSocket {
  this.events.removeListener(event, listener);
  }
  + // Add `off` method the socket which is called by the base class `DocumentDeltaConnection` to remove
  + // event listeners.
  + // We may have to add more methods from SocketIOClient.Socket if they start getting used.
  + public off(event: string, listener: (...args: any[]) => void) {
  + this.removeListener(event, listener);
  + return this;
  + }
  +
  public disconnect(close?: boolean) {
  for (const roomId of this.rooms) {
  this.server.pubsub.unsubscribe(roomId, this.subscriber);
  }
  + this._connected = false;
  this.emit("disconnect");
  }
  }
  