Don't examine jingleNode unless it's non-null.

remoting/webapp/me2mom/client_session.js

 // Copyright (c) 2011 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.
 
 /**
  * @fileoverview
  * Session class that handles creation and teardown of a remoting session.
  *
  * This abstracts a <embed> element and controls the plugin which does the
  * actual remoting work.  There should be no UI code inside this class.  It
@@ skipping 187 matching lines @@
   remoting.debug.log('Sending Iq: ' + msg);
 
   // Extract the top level fields of the Iq packet.
   // TODO(ajwong): Can the plugin just return these fields broken out.
   var parser = new DOMParser();
   var iqNode = parser.parseFromString(msg, 'text/xml').firstChild;
   var jingleNode = iqNode.firstChild;
   var serializer = new XMLSerializer();
   var parameters = {
     'to': iqNode.getAttribute('to') || '',
     'payload_xml': serializer.serializeToString(jingleNode),

[Sergey Ulanov, 2011/08/04 20:46:19]

Does this serialize null to an empty string?

[Jamie, 2011/08/04 20:46:57]

Yes.

     'id': iqNode.getAttribute('id') || '1',
     'type': iqNode.getAttribute('type'),
     'host_jid': this.hostJid
   };
 
   this.sendIqWithParameters_(parameters);
 
-  var action = jingleNode.getAttribute('action');
-  if (jingleNode.nodeName == 'jingle' && action == 'session-initiate') {
-    // The session id is needed in order to close the session later.
-    this.sessionId = jingleNode.getAttribute('sid');
+  if (jingleNode) {
+    var action = jingleNode.getAttribute('action');
+    if (jingleNode.nodeName == 'jingle' && action == 'session-initiate') {
+      // The session id is needed in order to close the session later.
+      this.sessionId = jingleNode.getAttribute('sid');
+    }
   }
 };
 
 /**
  * Sends an IQ stanza via the http xmpp proxy.
  *
  * @param {(string|Object.<string>)} paramters Parameters to include.
  * @return {void} Nothing.
  */
 remoting.ClientSession.prototype.sendIqWithParameters_ = function(parameters) {
@@ skipping 184 matching lines @@
     'video_bandwidth': this.plugin.videoBandwidth,
     'capture_latency': this.plugin.videoCaptureLatency,
     'encode_latency': this.plugin.videoEncodeLatency,
     'decode_latency': this.plugin.videoDecodeLatency,
     'render_latency': this.plugin.videoRenderLatency,
     'roundtrip_latency': this.plugin.roundTripLatency
   };
 };
 
 }());