[clutter/issue-17] wayland: Protect against enter events for empty surfaces

[Emmanuele Bassi <ebassi src gnome org>]

commit cd4c50db38ea9421deb83f25935a27531aa756a9
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Fri Mar 20 16:08:21 2020 +0000

    wayland: Protect against enter events for empty surfaces
    
    The `leave` handler checks for NULL surfaces, but the `enter` handler
    does not.
    
    Fixes: #17

 clutter/wayland/clutter-input-device-wayland.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/clutter/wayland/clutter-input-device-wayland.c b/clutter/wayland/clutter-input-device-wayland.c
index 7bfb615b7..3dab22070 100644
--- a/clutter/wayland/clutter-input-device-wayland.c
+++ b/clutter/wayland/clutter-input-device-wayland.c
@@ -472,7 +472,10 @@ clutter_wayland_handle_keyboard_enter (void *data,
                                        struct wl_array *keys)
 {
   ClutterInputDeviceWayland *device = data;
-  ClutterStageCogl          *stage_cogl;
+  ClutterStageCogl *stage_cogl;
+
+  if (surface == NULL)
+    return;
 
   if (!CLUTTER_IS_STAGE_COGL (wl_surface_get_user_data (surface)))
     return;
@@ -495,8 +498,9 @@ clutter_wayland_handle_keyboard_leave (void *data,
   ClutterInputDeviceWayland *device = data;
   ClutterStageCogl          *stage_cogl;
 
-  if (!surface)
+  if (surface == NULL)
     return;
+
   if (!CLUTTER_IS_STAGE_COGL (wl_surface_get_user_data (surface)))
     return;