[gnome-shell] lookingGlass: Avoid a little bit of RedBorderEffect overdraw

[Marge Bot <marge-bot src gnome org>]

commit 1879ca741e553655fc7f63b142310bb3b575f83b
Author: Daniel van Vugt <daniel van vugt canonical com>
Date:   Wed Jun 9 14:21:21 2021 +0800

    lookingGlass: Avoid a little bit of RedBorderEffect overdraw
    
    The left edge of the box was redrawing the bottom left corner when
    the bottom edge had already done so.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1876>

 js/ui/lookingGlass.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/js/ui/lookingGlass.js b/js/ui/lookingGlass.js
index 7604ae4a61..a9f0512dba 100644
--- a/js/ui/lookingGlass.js
+++ b/js/ui/lookingGlass.js
@@ -521,7 +521,7 @@ class RedBorderEffect extends Clutter.Effect {
         pipelineNode.add_rectangle(box);
 
         box.set_origin(0, width);
-        box.set_size(width, alloc.get_height() - width);
+        box.set_size(width, alloc.get_height() - width * 2);
         pipelineNode.add_rectangle(box);
     }
 });