Add setting for changing app icon style to symbolic

appIcons.js

@@ -63,6 +63,11 @@ let LABEL_GAP = 5;
 let MAX_INDICATORS = 4;
 export const DEFAULT_PADDING_SIZE = 4;
 
+let APPICON_STYLE = {
+    NORMAL: "NORMAL",
+    SYMBOLIC: "SYMBOLIC"
+}
+
 let DOT_STYLE = {
     DOTS: "DOTS",
     SQUARES: "SQUARES",
@@ -188,6 +193,7 @@ export const TaskbarAppIcon = GObject.registerClass({
 
         this._onAnimateAppiconHoverChanged();
         this._setAppIconPadding();
+        this._setAppIconStyle();
         this._showDots();
 
         this._focusWindowChangedId = global.display.connect('notify::focus-window', 
@@ -626,6 +632,15 @@ export const TaskbarAppIcon = GObject.registerClass({
         this._iconContainer.set_style('padding: ' + padding + 'px;');
     }
 
+    _setAppIconStyle() {
+        let symbolic_icon_style_name = 'symbolic-icon-style';
+        if (SETTINGS.get_string('appicon-style') === APPICON_STYLE.SYMBOLIC) {
+            this.add_style_class_name(symbolic_icon_style_name);
+        } else {
+            this.remove_style_class_name(symbolic_icon_style_name);
+        }
+    }
+
     popupMenu() {
         this._removeMenuTimeout();
         this.fake_release();