window: Add gtk_window_destroy

This is a replacement for gtk_widget_destroy for toplevels.
For now, it is just a wrapper.

docs/reference/gtk/gtk4-sections.txt

@@ -4190,6 +4190,7 @@ gtk_requisition_get_type
 GtkWindow
 GtkWindowClass
 gtk_window_new
+gtk_window_destroy
 gtk_window_get_child
 gtk_window_set_child
 gtk_window_set_title

gtk/gtkwindow.c

@@ -7516,3 +7516,17 @@ gtk_window_get_child (GtkWindow *window)
 
   return priv->child;
 }
+
+/**
+ * gtk_window_destroy:
+ * @window: The window to destroy
+ *
+ * Drop the internal reference GTK holds on toplevel windows.
+ */
+void
+gtk_window_destroy (GtkWindow *window)
+{
+  g_return_if_fail (GTK_IS_WINDOW (window));
+
+  gtk_widget_destroy (GTK_WIDGET (window));
+}

gtk/gtkwindow.h

@@ -254,6 +254,9 @@ GtkWidget *gtk_window_get_titlebar         (GtkWindow    *window);
 GDK_AVAILABLE_IN_ALL
 gboolean gtk_window_is_maximized           (GtkWindow    *window);
 
+GDK_AVAILABLE_IN_ALL
+void     gtk_window_destroy                (GtkWindow    *window);
+
 GDK_AVAILABLE_IN_ALL
 void     gtk_window_set_interactive_debugging (gboolean enable);