add active list to dock object

examples/appinfo/main.rs

@@ -0,0 +1,19 @@
+use gio::DesktopAppInfo;
+use glib::prelude::*;
+use glib::subclass;
+use glib::subclass::prelude::*;
+
+#[derive(Clone, Debug, PartialEq, Eq, glib::GBoxed)]
+#[gboxed(type_name = "MyBoxed")]
+struct MyBoxed(DesktopAppInfo);
+
+pub fn main() {
+    let appinfo = DesktopAppInfo::new("firefox.desktop").expect("failed to get app info");
+    assert!(MyBoxed::static_type().is_valid());
+
+    let b = MyBoxed(appinfo);
+    let v = b.to_value();
+    let b2 = v.get::<&MyBoxed>().unwrap();
+    assert_eq!(&b, b2);
+    dbg!(&b2.0.filename());
+}