fix: Drops the sys message handler after used or connected.

Drops the custom type breaking xmpp protocol.

modules/xmpp/strophe.jingle.js

      * Parses response when querying for services using urn:xmpp:extdisco:1 or urn:xmpp:extdisco:2.
      * Stores results in jvbIceConfig and p2pIceConfig.
      * @param res The response iq.
+     * @return {boolean} Whether something was processed from the supplied message.
      */
     onReceiveStunAndTurnCredentials(res) {
         const iceservers = [];
 
         this.jvbIceConfig.iceServers = iceservers.filter(filter);
         this.p2pIceConfig.iceServers = iceservers;
+
+        return iceservers.length > 0;
     }
 
     /**

modules/xmpp/xmpp.js

 
         this.eventEmitter.emit(XMPPEvents.CONNECTION_STATUS_CHANGED, credentials, status, msg);
         if (status === Strophe.Status.CONNECTED || status === Strophe.Status.ATTACHED) {
+            // once connected or attached we no longer need this handle, drop it if it exist
+            if (this._sysMessageHandler) {
+                this.connection._stropheConn.deleteHandler(this._sysMessageHandler);
+            }
+
             this.sendDiscoInfo && this.connection.jingle.getStunAndTurnCredentials();
 
             logger.info(`My Jabber ID: ${this.connection.jid}`);
         this.sendDiscoInfo = true;
 
         if (this.connection._stropheConn && this.connection._stropheConn._addSysHandler) {
-            this.connection._stropheConn._addSysHandler(msg => {
-                this.sendDiscoInfo = false;
-
-                this.connection.jingle.onReceiveStunAndTurnCredentials(msg);
-
-                const { features, identities } = parseDiscoInfo(msg);
-
-                this._processDiscoInfoIdentities(identities, features);
-
-                // check for shard name in identities
-                identities.forEach(i => {
-                    if (i.type === 'shard') {
-                        this.options.deploymentInfo.shard = i.name;
-                    }
-                });
-            }, null, 'message', 'service-info', null);
+            this._sysMessageHandler = this._onSystemMessage.bind(this);
+            this.connection._stropheConn._addSysHandler(this._sysMessageHandler, null, 'message');
         } else {
             logger.warn('Cannot attach strophe system handler, jiconop cannot operate');
         }
             }));
     }
 
+    /**
+     * Receives system messages during the connect/login process and checks for services or
+     * @param msg The received message.
+     * @returns {void}
+     * @private
+     */
+    _onSystemMessage(msg) {
+        this.sendDiscoInfo = false;
+
+        const foundIceServers = this.connection.jingle.onReceiveStunAndTurnCredentials(msg);
+
+        const { features, identities } = parseDiscoInfo(msg);
+
+        this._processDiscoInfoIdentities(identities, features);
+
+        // check for shard name in identities
+        identities.forEach(i => {
+            if (i.type === 'shard') {
+                this.options.deploymentInfo.shard = i.name;
+            }
+        });
+
+        if (foundIceServers || identities.size > 0 || features.size > 0) {
+            this.connection._stropheConn.deleteHandler(this._sysMessageHandler);
+            this._sysMessageHandler = null;
+        }
+    }
+
     /**
      * Attach to existing connection. Can be used for optimizations. For
      * example: if the connection is created on the server we can attach to it