[gnome-shell] lookingGlass: Paint the RedBorderEffect right edge the correct height

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

commit d8802aafc43387974b0e0e22f765468776d8f40f
Author: Daniel van Vugt <daniel van vugt canonical com>
Date:   Wed Jun 9 14:09:51 2021 +0800

    lookingGlass: Paint the RedBorderEffect right edge the correct height
    
    It was being painted one box thickness (`width`) too tall so you could
    see a rendering glitch below the bottom right corner until now.
    
    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 e59fa29306..7604ae4a61 100644
--- a/js/ui/lookingGlass.js
+++ b/js/ui/lookingGlass.js
@@ -513,7 +513,7 @@ class RedBorderEffect extends Clutter.Effect {
         pipelineNode.add_rectangle(box);
 
         box.set_origin(alloc.get_width() - width, width);
-        box.set_size(width, alloc.get_height());
+        box.set_size(width, alloc.get_height() - width);
         pipelineNode.add_rectangle(box);
 
         box.set_origin(0, alloc.get_height() - width);