[gtk+] wayland: fix filechooser crash

[Matthias Clasen <matthiasc src gnome org>]

commit 44023353336c9dd595022ec7eceb1f927f859d93
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Aug 23 10:27:43 2017 -0400

    wayland: fix filechooser crash
    
    The size of the window can be updated before we're requested its
    creation on the compositor.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786673

 gdk/wayland/gdkwindow-wayland.c |   10 +++-------
 1 files changed, 3 insertions(+), 7 deletions(-)
---
diff --git a/gdk/wayland/gdkwindow-wayland.c b/gdk/wayland/gdkwindow-wayland.c
index 8af96e1..1b01534 100644
--- a/gdk/wayland/gdkwindow-wayland.c
+++ b/gdk/wayland/gdkwindow-wayland.c
@@ -331,13 +331,9 @@ gdk_wayland_window_update_size (GdkWindow *window,
   impl->scale = scale;
 
   if (impl->display_server.egl_window)
-    {
-      wl_egl_window_resize (impl->display_server.egl_window,
-                            width * scale,
-                            height * scale,
-                            0, 0);
-    }
-  wl_surface_set_buffer_scale (impl->display_server.wl_surface, scale);
+    wl_egl_window_resize (impl->display_server.egl_window, width * scale, height * scale, 0, 0);
+  if (impl->display_server.wl_surface)
+    wl_surface_set_buffer_scale (impl->display_server.wl_surface, scale);
 
   area.x = 0;
   area.y = 0;