Move running_box to Launcher

Author: danirabbit

src/AppSystem/Launcher.vala

@@ -60,6 +60,7 @@ public class Dock.Launcher : BaseItem {
         }
     }
 
+    private Gtk.Box running_box;
     private Gtk.Image image;
     private Gtk.Label badge;
     private Gtk.Revealer progress_revealer;

src/BaseItem.vala

@@ -54,7 +54,6 @@ public class Dock.BaseItem : Gtk.Box {
 
     protected Gtk.Overlay overlay;
     protected Gtk.GestureClick gesture_click;
-    protected Gtk.Box running_box;
 
     protected Granite.Bin bin { get; private set; }