volume: let GTK theme control icon sizes, remove icon-size config

data/style/widgets/volume.scss

-:root {
-  --widget-volume-row-icon-size: 24px;
-}
-
 .widget-volume {
 }
 
 .widget-volume>box>button {}
 
-/* Each row app icon */
-.widget-volume row image {
-  -gtk-icon-size: var(--widget-volume-row-icon-size);
-}
-
 .per-app-volume {
   background-color: var(--noti-bg-alt);
   margin: $margin;

src/configSchema.json

@@ -682,12 +682,6 @@
           "default": "⇩",
           "description": "Label displayed on button to hide per app volume control"
         },
-        "icon-size": {
-          "type": "integer",
-          "deprecated": true,
-          "default": -1,
-          "description": "deprecated (change the CSS root variable \"--widget-volume-row-icon-size\"): Size of the application icon in per app volume control"
-        },
         "animation-type": {
           "type": "string",
           "default": "slide_down",

src/controlCenter/widgets/volume/sinkInputRow.vala

@@ -13,7 +13,7 @@ namespace XimperShellNotificationCenter.Widgets {
         private bool show_per_app_label;
 
         public SinkInputRow (PulseSinkInput sink_input, PulseDaemon client,
-                             int icon_size, bool show_per_app_icon, bool show_per_app_label) {
+                             bool show_per_app_icon, bool show_per_app_label) {
             this.client = client;
             this.show_per_app_icon = show_per_app_icon;
             this.show_per_app_label = show_per_app_label;
@@ -25,8 +25,6 @@ namespace XimperShellNotificationCenter.Widgets {
             scale.draw_value = false;
             scale.set_hexpand (true);
 
-            icon.set_pixel_size (icon_size);
-
             container = new Gtk.Box (Gtk.Orientation.HORIZONTAL, 0);
 
             if (show_per_app_icon) {

src/controlCenter/widgets/volume/volume.vala

@@ -21,8 +21,6 @@ namespace XimperShellNotificationCenter.Widgets {
         string ?expand_label = null;
         string ?collapse_label = null;
 
-        [Version (deprecated = true, replacement = "CSS root variable")]
-        int icon_size = -1;
 
         Gtk.RevealerTransitionType revealer_type = Gtk.RevealerTransitionType.SLIDE_DOWN;
         int revealer_duration = 250;
@@ -99,11 +97,6 @@ namespace XimperShellNotificationCenter.Widgets {
                     collapse_label = l2;
                 }
 
-                int i = int.max (get_prop<int> (config, "icon-size"), 0);
-                if (i != 0) {
-                    icon_size = i;
-                }
-
                 revealer_duration = int.max (0, get_prop<int> (config, "animation-duration"));
                 if (revealer_duration == 0) {
                     revealer_duration = 250;
@@ -154,7 +147,7 @@ namespace XimperShellNotificationCenter.Widgets {
 
                 foreach (var item in this.client.active_sinks.values) {
                     SinkInputRow row = new SinkInputRow (item, client,
-                                                         icon_size, show_per_app_icon,
+                                                         show_per_app_icon,
                                                          show_per_app_label);
                     list_box_controller.append (row);
                 }
@@ -245,7 +238,7 @@ namespace XimperShellNotificationCenter.Widgets {
                 list_box_controller.remove ((Gtk.Widget) label);
             }
             SinkInputRow row = new SinkInputRow (sink, client,
-                                                 icon_size, show_per_app_icon,
+                                                 show_per_app_icon,
                                                  show_per_app_label);
             list_box_controller.append (row);
         }