appDisplay: Revisit "Add drop shadow to icons"

The shadow is barely visible on dark backgrounds, but it's not
wrong to be consistent with Settings, Software and GNOME Classic.

With the app icon swarm animation gon, the performance implications might not be as critical (https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/3124

- increase blur but not much, while we can't have multi-layered shadows.

Fixes https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/3670
Also see https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/3123

data/theme/gnome-shell-sass/widgets/_base.scss

@@ -14,5 +14,5 @@
 
 // Dropshadow for large icons
 .icon-dropshadow {
-  icon-shadow: 0 1px 2px rgba(black, 0.4);
+  icon-shadow: 0 1px 5px rgba(black, 0.8);
 }

js/ui/appDisplay.js

@@ -1424,7 +1424,11 @@ var AppSearchProvider = class AppSearchProvider {
                 metas.push({
                     id: app.get_id(),
                     name: app.get_name(),
-                    createIcon: size => app.create_icon_texture(size),
+                    createIcon: size => {
+                        const icon = app.create_icon_texture(size);
+                        icon.add_style_class_name('icon-dropshadow');
+                        return icon;
+                    },
                 });
             } else {
                 let name = this._systemActions.getName(id);
@@ -2688,7 +2692,9 @@ var AppIcon = GObject.registerClass({
     }
 
     _createIcon(iconSize) {
-        return this.app.create_icon_texture(iconSize);
+        const icon = this.app.create_icon_texture(iconSize);
+        icon.add_style_class_name('icon-dropshadow');
+        return icon;
     }
 
     _removeMenuTimeout() {

js/ui/dash.js

@@ -468,6 +468,7 @@ var Dash = GObject.registerClass({
         item.setLabelText(app.get_name());
 
         appIcon.icon.setIconSize(this.iconSize);
+        appIcon.icon.add_style_class_name('icon-dropshadow');
         this._hookUpLabel(item, appIcon);
 
         return item;