Fix Vala for Ubuntu 22.04

Author: wmww

examples/meson.build

@@ -20,6 +20,11 @@ if get_option('vapi')
         'simple-example-vala',
         files('simple-example.vala'),
         dependencies: [gtk, gtk_layer_shell, vapi],
-        c_args: ['-Wno-unused-but-set-variable', '-Wno-unused-parameter', '-Wno-cast-function-type'],
+        c_args: [
+            '-Wno-unused-but-set-variable',
+            '-Wno-unused-parameter',
+            '-Wno-cast-function-type',
+            '-Wno-deprecated-declarations',
+        ],
         install: false)
 endif

examples/simple-example.vala

@@ -4,7 +4,7 @@ using GtkLayerShell;
 int main(string[] argv) {
     var app = new Gtk.Application (
         "com.github.wmww.gtk4-layer-shell.vala-example",
-        GLib.ApplicationFlags.DEFAULT_FLAGS);
+        GLib.ApplicationFlags.FLAGS_NONE);
 
     app.activate.connect (() => {
         var window = new Gtk.ApplicationWindow (app);