Fix a typo.

modules/UI/UI.js

     APP.xmpp.addListener(XMPPEvents.SUBJECT_CHANGED, chatSetSubject);
     APP.xmpp.addListener(XMPPEvents.MESSAGE_RECEIVED, updateChatConversation);
     APP.xmpp.addListener(XMPPEvents.MUC_LEFT, onMucLeft);
-    APP.xmpp.addListener(XMPPEvents.PASSWORD_REQUIRED, onPasswordReqiured);
+    APP.xmpp.addListener(XMPPEvents.PASSWORD_REQUIRED, onPasswordRequired);
     APP.xmpp.addListener(XMPPEvents.CHAT_ERROR_RECEIVED, chatAddError);
     APP.xmpp.addListener(XMPPEvents.ETHERPAD, initEtherpad);
     APP.xmpp.addListener(XMPPEvents.AUTHENTICATION_REQUIRED,
     }
 };
 
-function onPasswordReqiured(callback) {
+function onPasswordRequired(callback) {
     // password is required
     Toolbar.lockLockButton();
     var message = '<h2 data-i18n="dialog.passwordRequired">';