Fix assert in remoting.XmppConnection

remoting/webapp/crd/js/xmpp_connection.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 'use strict';
 
 /** @suppress {duplicate} */
 var remoting = remoting || {};
 
 /**
@@ skipping 307 matching lines @@
     }
 
     // Once fake SSL handshake is finished pass the data to the login handler.
     if (!this.fakeSslHandshake_ && data.byteLength > 0) {
       this.loginHandler_.onDataReceived(data);
     }
   } else if (this.state_ == remoting.SignalStrategy.State.CONNECTED) {
     this.streamParser_.appendData(readInfo.data);
   }
 
-  if (!this.startTlsPending_) {
+  if (!this.startTlsPending_ &&
+      this.state_ != remoting.SignalStrategy.State.CLOSED) {
     this.tryRead_();
   }
 };
 
 /**
  * @param {string} text
  * @private
  */
 remoting.XmppConnection.prototype.sendString_ = function(text) {
   this.sendBuffer_(base.encodeUtf8(text));
@@ skipping 141 matching lines @@
 /**
  * @param {remoting.SignalStrategy.State} newState
  * @private
  */
 remoting.XmppConnection.prototype.setState_ = function(newState) {
   if (this.state_ != newState) {
     this.state_ = newState;
     this.onStateChangedCallback_(this.state_);
   }
 };