[mutter/wayland] wayland: Allow destroying the wl_surface before the xdg_surface

[Jasper St. Pierre <jstpierre src gnome org>]

commit 7ef8d21e48438296da066111bdd4c98a5304fb14
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Tue Feb 18 22:21:33 2014 -0500

    wayland: Allow destroying the wl_surface before the xdg_surface
    
    As resource destruction can happen in any order at shutdown, we
    need to be flexible here. A client disconnecting without cleaning
    up all its resources should not assert fail.

 src/wayland/meta-wayland-surface.c |   21 ++++++++++++---------
 1 files changed, 12 insertions(+), 9 deletions(-)
---
diff --git a/src/wayland/meta-wayland-surface.c b/src/wayland/meta-wayland-surface.c
index 10767cf..e8777df 100644
--- a/src/wayland/meta-wayland-surface.c
+++ b/src/wayland/meta-wayland-surface.c
@@ -596,11 +596,14 @@ meta_wayland_surface_window_unmanaged (MetaWaylandSurface *surface)
 static void
 destroy_window (MetaWaylandSurface *surface)
 {
-  MetaDisplay *display = meta_get_display ();
-  guint32 timestamp = meta_display_get_current_time_roundtrip (display);
+  if (surface->window)
+    {
+      MetaDisplay *display = meta_get_display ();
+      guint32 timestamp = meta_display_get_current_time_roundtrip (display);
+
+      meta_window_unmanage (surface->window, timestamp);
+    }
 
-  g_assert (surface->window != NULL);
-  meta_window_unmanage (surface->window, timestamp);
   g_assert (surface->window == NULL);
 }
 
@@ -610,11 +613,11 @@ wl_surface_destructor (struct wl_resource *resource)
   MetaWaylandSurface *surface = wl_resource_get_user_data (resource);
   MetaWaylandCompositor *compositor = surface->compositor;
 
-  /* At the time when the wl_surface is destroyed, we should
-   * no longer have a window, unless we're an XWayland window
-   * in which case we received the wl_surface.destroy before
-   * the UnmapNotify/DestroyNotify. */
-  g_assert (surface->window == NULL || surface->window->client_type == META_WINDOW_CLIENT_TYPE_X11);
+  /* If we still have a window at the time of destruction, that means that
+   * the client is disconnecting, as the resources are destroyed in a random
+   * order. Simply destroy the window in this case. */
+  if (surface->window)
+    destroy_window (surface);
 
   compositor->surfaces = g_list_remove (compositor->surfaces, surface);