wayland: Reset server decoration interface on window mapping

The wl_surface is destroyed and recreated when the window is
mapped/unmapped. As we have a new wl_surface we need to create a new
server_decoration object for that surface.

gdk/wayland/gdkwindow-wayland.c

@@ -2938,11 +2938,13 @@ gdk_wayland_window_map (GdkWindow *window)
       else
         {
           gdk_wayland_window_create_xdg_toplevel (window);
+          gdk_wayland_window_announce_decoration_mode (window);
         }
     }
   else
     {
       gdk_wayland_window_create_xdg_toplevel (window);
+      gdk_wayland_window_announce_decoration_mode (window);
     }
 
   impl->mapped = TRUE;