[gnome-shell] sessionMode: Add back external session modes

[Florian Müllner <fmuellner src gnome org>]

commit 8e668ca6332abfe286b82c14d4f78810e052ca68
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Dec 6 21:31:46 2013 +0100

    sessionMode: Add back external session modes
    
    Since commit da4238ec681c7ca, external session modes are no longer
    loaded during start-up; bring them back.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=720017

 js/ui/sessionMode.js |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/js/ui/sessionMode.js b/js/ui/sessionMode.js
index 7b8bc17..69715e4 100644
--- a/js/ui/sessionMode.js
+++ b/js/ui/sessionMode.js
@@ -148,6 +148,7 @@ const SessionMode = new Lang.Class({
     Name: 'SessionMode',
 
     _init: function() {
+        _loadModes();
         let isPrimary = (_modes[global.session_mode] &&
                          _modes[global.session_mode].isPrimary);
         let mode = isPrimary ? global.session_mode : 'user';