Converts some services to use aura-mus

ui/aura/mus/window_port_mus.cc

Index: ui/aura/mus/window_port_mus.cc
diff --git a/ui/aura/mus/window_port_mus.cc b/ui/aura/mus/window_port_mus.cc
index 35fab977ef5be4b9841408de7b07407b71a8f81f..da5774c1935d7a7a56b1a23f5c0734bb665636cc 100644
--- a/ui/aura/mus/window_port_mus.cc
+++ b/ui/aura/mus/window_port_mus.cc
@@ -65,6 +65,13 @@ void WindowPortMus::SetPredefinedCursor(ui::mojom::Cursor cursor_id) {
   predefined_cursor_ = cursor_id;
 }
 
+void WindowPortMus::Embed(
+    ui::mojom::WindowTreeClientPtr client,
+    uint32_t flags,
+    const ui::mojom::WindowTree::EmbedCallback& callback) {
+  window_tree_client_->Embed(window_, std::move(client), flags, callback);
+}
+
 std::unique_ptr<WindowCompositorFrameSink>
 WindowPortMus::RequestCompositorFrameSink(
     ui::mojom::CompositorFrameSinkType type,