[gnome-shell] Fix XDND regression

[Adel Gadllah <agadllah src gnome org>]

commit 340609d149b93469a4e0b74d5379691767148dff
Author: Adel Gadllah <adel gadllah gmail com>
Date:   Sun Feb 17 20:45:14 2013 +0100

    Fix XDND regression
    
    The top_window_group blocks the panel elements from being found by the XDND
    pick so hide the whole group from picks as we never attempt to pick its contents
    anyway.

 js/ui/layout.js |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/js/ui/layout.js b/js/ui/layout.js
index d181bf6..edcb0e1 100644
--- a/js/ui/layout.js
+++ b/js/ui/layout.js
@@ -207,6 +207,11 @@ const LayoutManager = new Lang.Class({
         global.stage.remove_actor(global.top_window_group);
         this.uiGroup.add_actor(global.top_window_group);
 
+        // This blocks the XDND picks from finding the activities button
+        // and we never attempt to pick anything from it anyway so make
+        // it invisible from picks
+        Shell.util_set_hidden_from_pick(global.top_window_group, true);
+
         // Need to update struts on new workspaces when they are added
         global.screen.connect('notify::n-workspaces',
                               Lang.bind(this, this._queueUpdateRegions));