[gnome-shell] windowManager: Change effect's brightness property

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit 928595fe21f7f076114123de2dcc9adb64d3425e
Author: Florian Müllner <fmuellner gnome org>
Date:   Sun Jul 22 03:31:54 2018 +0200

    windowManager: Change effect's brightness property
    
    The set_brightness() method is the most convenient way of controlling
    the effect's brightness, but Clutter animations only deal with properties,
    so start using the (ClutterColor) brightness property instead.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/666

 js/ui/windowManager.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)
---
diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index f7e4dc211..1d1f244ad 100644
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -127,7 +127,8 @@ var WindowDimmer = class {
     }
 
     _syncEnabled() {
-        this._brightnessEffect.enabled = (this._enabled && this._dimFactor > 0);
+        let dimmed = this._brightnessEffect.brightness.red != 127;
+        this._brightnessEffect.enabled = (this._enabled && dimmed);
     }
 
     setEnabled(enabled) {
@@ -144,14 +145,17 @@ var WindowDimmer = class {
                 time: (dimmed ? DIM_TIME : UNDIM_TIME) / 1000,
                 transition: 'linear',
                 onUpdate: () => {
-                    let brightness = this._dimFactor * DIM_BRIGHTNESS;
-                    this._brightnessEffect.set_brightness(brightness);
+                    let val = 127 * (1 + this._dimFactor * DIM_BRIGHTNESS);
+                    let color = Clutter.Color.new(val, val, val, 255);
+                    this._brightnessEffect.brightness = color;
                     this._syncEnabled();
                 }
             });
         } else {
             this._dimFactor = factor;
-            this._brightnessEffect.set_brightness(factor * DIM_BRIGHTNESS);
+            let val = 127 * (1 + this._dimFactor * DIM_BRIGHTNESS);
+            let color = Clutter.Color.new(val, val, val, 255);
+            this._brightnessEffect.brightness = color;
             this._syncEnabled();
         }
     }