[gnome-shell] ScreenShield: fix regression in GDM greeter

[Giovanni Campagna <gcampagna src gnome org>]

commit 5c4570fcaa7cffaecb4534fa3fb6749e894e5f76
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Thu Jan 31 16:56:24 2013 +0100

    ScreenShield: fix regression in GDM greeter
    
    The initial state of the lock screen is HIDDEN, and hideLockScreen
    enforces that now, so reflect it in Clutter state too.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=692948

 js/ui/screenShield.js |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/js/ui/screenShield.js b/js/ui/screenShield.js
index 9043bc3..b972eaa 100644
--- a/js/ui/screenShield.js
+++ b/js/ui/screenShield.js
@@ -454,6 +454,7 @@ const ScreenShield = new Lang.Class({
                                                 reactive: true,
                                                 can_focus: true,
                                                 name: 'lockScreenGroup',
+                                                visible: false,
                                               });
         this._lockScreenGroup.connect('key-release-event',
                                       Lang.bind(this, this._onLockScreenKeyRelease));