[gnome-shell] lightbox: Change vignette brightness to 0.5

[Florian Müllner <fmuellner src gnome org>]

commit 765895fb19fc775da4ffef50e4c376c743f3758d
Author: Jonas Dreßler <verdre v0yd nl>
Date:   Sun Jan 19 18:01:57 2020 +0100

    lightbox: Change vignette brightness to 0.5
    
    Since the overview search results now have a dark background layer, we
    can brighten the background image a bit again. As a factor we use 0.5,
    since that ensures the texts in the IconGrid are still readable and the
    background image is visible, too.
    
    Fixes https://gitlab.gnome.org/GNOME/gnome-shell/issues/2133

 js/ui/lightbox.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/js/ui/lightbox.js b/js/ui/lightbox.js
index 5446696a8b..4f265af42b 100644
--- a/js/ui/lightbox.js
+++ b/js/ui/lightbox.js
@@ -6,7 +6,7 @@ const { Clutter, GObject, Shell, St } = imports.gi;
 const Params = imports.misc.params;
 
 var DEFAULT_FADE_FACTOR = 0.4;
-var VIGNETTE_BRIGHTNESS = 0.2;
+var VIGNETTE_BRIGHTNESS = 0.5;
 var VIGNETTE_SHARPNESS = 0.7;
 
 const VIGNETTE_DECLARATIONS = '\