gwl: Bring back slider buttons

Author: anaximeno

data/theme/cinnamon-sass/widgets/_windowlist.scss

@@ -109,13 +109,29 @@
   }
 
   &-scrollbox {
-    &.vfade {
-      -st-vfade-offset: 68px;
-      -st-hfade-offset: 0;
+    &-scrollview {
+      &.vfade {
+        -st-vfade-offset: 48px;
+        -st-hfade-offset: 0;
+      }
+      &.hfade {
+        -st-hfade-offset: 48px;
+        -st-vfade-offset: 0;
+      }
     }
-    &.hfade {
-      -st-hfade-offset: 68px;
-      -st-vfade-offset: 0;
+
+    &-button {
+      &-start,
+      &-end,
+      &-up,
+      &-down {
+        margin: 0;
+        padding: 0;
+      }
+
+      &-icon {
+        icon-size: $scalable_icon_size;
+      }
     }
   }
 }

files/usr/share/cinnamon/applets/grouped-window-list@cinnamon.org/applet.js

@@ -799,8 +799,8 @@ class GroupedWindowListApplet extends Applet.Applet {
         let adjustmentValue = 0;
         if (currentWorkspace.scrollBox) {
             const adjustment = this.state.isHorizontal ?
-                currentWorkspace.scrollBox.actor.get_hscroll_bar().get_adjustment() :
-                currentWorkspace.scrollBox.actor.get_vscroll_bar().get_adjustment();
+                currentWorkspace.scrollBox.scrollView.get_hscroll_bar().get_adjustment() :
+                currentWorkspace.scrollBox.scrollView.get_vscroll_bar().get_adjustment();
             adjustmentValue = adjustment.get_value();
         }