Call plugin.onIq() only when onIq is not null.

remoting/webapp/me2mom/client_session.js

Index: remoting/webapp/me2mom/client_session.js
diff --git a/remoting/webapp/me2mom/client_session.js b/remoting/webapp/me2mom/client_session.js
index 9fcd4d950ff4663a3e80086f841eee7fc4b2c1ff..9de2f37fa0df6ea19e8a93d581b8c53d6f410970 100644
--- a/remoting/webapp/me2mom/client_session.js
+++ b/remoting/webapp/me2mom/client_session.js
@@ -272,7 +272,8 @@ remoting.ClientSession.prototype.connectPluginToWcs_ =
   /** @param {string} stanza The IQ stanza received. */
   var onIq = function(stanza) {
     remoting.debug.logIq(false, stanza);
-    that.plugin.onIq(stanza);
+    if (that.plugin.onIq)

[Wez, 2011/11/19 00:59:14]

Do we want to log something different if there is no onIq(), so we can tell that
the message wasn't sent?

[garykac, 2011/11/19 01:12:49]

+1
We shouldn't be logging the stanza if we didn't actually send it.
Or we should note that we were unable to send the stanza.

[Sergey Ulanov, 2011/11/19 01:30:53]

This function handles incoming messages, not outgoing, i.e. it doesn't send
anything. onIq isn't set here after the plugin has been shut down after
disconnection, so I don't think it's not very important to log this event here.
Added log message anyway.

[Sergey Ulanov, 2011/11/19 01:30:53]

We don't send anything here, it's for incoming messages.

+      that.plugin.onIq(stanza);
   }
   remoting.wcs.setOnIq(onIq);
   that.plugin.connect(this.hostJid, this.hostPublicKey, this.clientJid,