[gnome-shell] layout: Use monitor index when adding bg managers

[Adel Gadllah <agadllah src gnome org>]

commit 15ab285174901e20d251265436055c11aee8398e
Author: Adel Gadllah <adel gadllah gmail com>
Date:   Wed Oct 2 15:48:39 2013 +0200

    layout: Use monitor index when adding bg managers
    
    Don't assume that this._bgManagers.push() (i.e adding to the end) is always
    correct.
    
    On startup we call _createPrimaryBackground which passes in the primary index
    which may not be 0.

 js/ui/layout.js |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/js/ui/layout.js b/js/ui/layout.js
index 9024695..1271709 100644
--- a/js/ui/layout.js
+++ b/js/ui/layout.js
@@ -362,7 +362,7 @@ const LayoutManager = new Lang.Class({
                               BackgroundMenu.addBackgroundMenu(bgManager.background.actor);
                           }));
 
-        this._bgManagers.push(bgManager);
+        this._bgManagers[monitorIndex] = bgManager;
 
         return bgManager.background;
     },