[gnome-shell] overview: remove outdated comment

[Giovanni Campagna <gcampagna src gnome org>]

commit 04f1f5f94b4dbd0b2e2a564b01792befbd1c69ea
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Sat May 25 14:59:43 2013 +0200

    overview: remove outdated comment
    
    Visibility of global.window_group is handled in layout.js nowadays.

 js/ui/overview.js |    9 ---------
 1 files changed, 0 insertions(+), 9 deletions(-)
---
diff --git a/js/ui/overview.js b/js/ui/overview.js
index 99814ac..3fd3aa1 100644
--- a/js/ui/overview.js
+++ b/js/ui/overview.js
@@ -512,15 +512,6 @@ const Overview = new Lang.Class({
         this.visibleTarget = true;
         this._activationTime = Date.now() / 1000;
 
-        // All the the actors in the window group are completely obscured,
-        // hiding the group holding them while the Overview is displayed greatly
-        // increases performance of the Overview especially when there are many
-        // windows visible.
-        //
-        // If we switched to displaying the actors in the Overview rather than
-        // clones of them, this would obviously no longer be necessary.
-        //
-        // Disable unredirection while in the overview
         Meta.disable_unredirect_for_screen(global.screen);
         this._viewSelector.show();