[gtk+] wayland: don't change the cursor if there is no pointer

[Matthias Clasen <matthiasc src gnome org>]

commit 6de2c7fa0e1738e180e47c6687aa31c98bf1891d
Author: Emilio Pozuelo Monfort <emilio pozuelo collabora co uk>
Date:   Mon Jun 23 18:21:08 2014 +0200

    wayland: don't change the cursor if there is no pointer
    
    https://bugzilla.gnome.org/show_bug.cgi?id=732206

 gdk/wayland/gdkdevice-wayland.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/gdk/wayland/gdkdevice-wayland.c b/gdk/wayland/gdkdevice-wayland.c
index 327c124..9471d31 100644
--- a/gdk/wayland/gdkdevice-wayland.c
+++ b/gdk/wayland/gdkdevice-wayland.c
@@ -183,6 +183,10 @@ gdk_wayland_device_update_window_cursor (GdkWaylandDeviceData *wd)
 
   buffer = _gdk_wayland_cursor_get_buffer (wd->cursor, wd->cursor_image_index,
                                            &x, &y, &w, &h, &scale);
+
+  if (!wd->wl_pointer)
+    return FALSE;
+
   wl_pointer_set_cursor (wd->wl_pointer,
                          wd->enter_serial,
                          wd->pointer_surface,