[mutter] wayland: Use clutter_input_device_is_grouped() for tablet grouping

[Carlos Garnacho <carlosg src gnome org>]

commit 29b240e8838cf923ff0f5c8a7b380b035c23f4bb
Author: Carlos Garnacho <carlosg gnome org>
Date:   Mon Feb 13 11:59:44 2017 +0100

    wayland: Use clutter_input_device_is_grouped() for tablet grouping
    
    Instead of poking the internal libinput device.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=779986

 src/wayland/meta-wayland-tablet-seat.c |   19 ++-----------------
 1 files changed, 2 insertions(+), 17 deletions(-)
---
diff --git a/src/wayland/meta-wayland-tablet-seat.c b/src/wayland/meta-wayland-tablet-seat.c
index 5e34ad3..e6390e3 100644
--- a/src/wayland/meta-wayland-tablet-seat.c
+++ b/src/wayland/meta-wayland-tablet-seat.c
@@ -482,14 +482,7 @@ lookup_grouped_devices (ClutterInputDevice     *device,
   ClutterDeviceManager *device_manager;
   const GSList *devices, *l;
   GList *group = NULL;
-  MetaBackend *backend = meta_get_backend ();
 
-#ifdef HAVE_NATIVE_BACKEND
-  struct libinput_device *dev = NULL, *libinput_device;
-
-  if (META_IS_BACKEND_NATIVE (backend))
-    dev = clutter_evdev_input_device_get_libinput_device (device);
-#endif
   device_manager = clutter_device_manager_get_default ();
   devices = clutter_device_manager_peek_devices (device_manager);
 
@@ -500,16 +493,8 @@ lookup_grouped_devices (ClutterInputDevice     *device,
       if (clutter_input_device_get_device_type (l->data) != type)
         continue;
 
-#ifdef HAVE_NATIVE_BACKEND
-      if (META_IS_BACKEND_NATIVE (backend))
-        {
-          libinput_device = clutter_evdev_input_device_get_libinput_device (l->data);
-
-          if (libinput_device_get_device_group (dev) !=
-              libinput_device_get_device_group (libinput_device))
-            continue;
-        }
-#endif
+      if (!clutter_input_device_is_grouped (device, l->data))
+        continue;
 
       group = g_list_prepend (group, l->data);
     }