Use Meta.WaylandClient for shell components

src/PantheonShell.vala

@@ -0,0 +1,46 @@
+public class Gala.PantheonShell : Object {
+    public static void init (Meta.Display display) requires (instance == null) {
+        instance = new PantheonShell (display);
+    }
+
+    private static PantheonShell? instance = null;
+
+    public Meta.Display display { get; construct; }
+
+    private Meta.WaylandClient dock_client;
+
+    private PantheonShell (Meta.Display display) {
+        Object (display: display);
+    }
+
+    construct {
+        display.window_created.connect ((window) => {
+            if (dock_client != null && dock_client.owns_window (window)) {
+                setup_dock_window (window);
+            }
+        });
+
+        var subprocess_launcher = new GLib.SubprocessLauncher (NONE);
+        try {
+            dock_client = new Meta.WaylandClient (subprocess_launcher);
+            string[] args = {"io.elementary.dock"};
+            dock_client.spawnv (display, args);
+        } catch (Error e) {
+            warning ("Failed to create dock client: %s", e.message);
+        }
+    }
+
+    private void setup_dock_window (Meta.Window window) {
+        window.notify["above"].connect (() => {
+            if (!window.above) {
+                window.make_above ();
+            }
+        });
+
+        window.shown.connect (() => {
+            window.move_frame (false, 0, 0);
+            window.move_to_monitor (display.get_primary_monitor ());
+            window.make_above ();
+        });
+    }
+}

src/WindowManager.vala

@@ -369,6 +369,8 @@ namespace Gala {
 
                 plugin_manager.load_waiting_plugins ();
 
+                PantheonShell.init (display);
+
                 return false;
             });
 

src/meson.build

@@ -9,6 +9,7 @@ gala_bin_sources = files(
     'Main.vala',
     'MediaFeedback.vala',
     'NotificationStack.vala',
+    'PantheonShell.vala',
     'PluginManager.vala',
     'ScreenSaverManager.vala',
     'ScreenshotManager.vala',