Adds not allowed errors and handling it.

JitsiConferenceErrors.js

  * Indicates that a connection error occurred when trying to join a conference.
  */
 export const CONNECTION_ERROR = "conference.connectionError";
+/**
+ * Indicates that a connection error is due to not allowed,
+ * occurred when trying to join a conference.
+ */
+export const NOT_ALLOWED_ERROR = "conference.connectionError.notAllowed";
 /**
  * Indicates that focus error happened.
  */

JitsiConferenceEventManager.js

     this.chatRoomForwarder.forward(XMPPEvents.ROOM_CONNECT_ERROR,
         JitsiConferenceEvents.CONFERENCE_FAILED,
         JitsiConferenceErrors.CONNECTION_ERROR);
+    this.chatRoomForwarder.forward(XMPPEvents.ROOM_CONNECT_NOT_ALLOWED_ERROR,
+        JitsiConferenceEvents.CONFERENCE_FAILED,
+        JitsiConferenceErrors.NOT_ALLOWED_ERROR);
 
     this.chatRoomForwarder.forward(XMPPEvents.ROOM_MAX_USERS_ERROR,
         JitsiConferenceEvents.CONFERENCE_FAILED,

modules/xmpp/ChatRoom.js

 
         } else {
             logger.warn('onPresError ', pres);
-            this.eventEmitter.emit(XMPPEvents.ROOM_CONNECT_ERROR);
+            this.eventEmitter.emit(XMPPEvents.ROOM_CONNECT_NOT_ALLOWED_ERROR);
         }
     } else if($(pres).find('>error>service-unavailable').length) {
         logger.warn('Maximum users limit for the room has been reached',

service/xmpp/XMPPEvents.js

     REMOTE_TRACK_REMOVED: "xmpp.remote_track_removed",
     RESERVATION_ERROR: "xmpp.room_reservation_error",
     ROOM_CONNECT_ERROR: 'xmpp.room_connect_error',
+    ROOM_CONNECT_NOT_ALLOWED_ERROR: 'xmpp.room_connect_error.not_allowed',
     ROOM_JOIN_ERROR: 'xmpp.room_join_error',
     /**
      * Indicates that max users limit has been reached.