[mutter] virtual-input-device/native: Verify device cleanup in impl_state_free()

[Marge Bot <marge-bot src gnome org>]

commit 9de36fed4dfa392b5c826fc73b97467c754d2e3c
Author: Jonas Ådahl <jadahl gmail com>
Date:   Tue Jan 26 23:02:26 2021 +0100

    virtual-input-device/native: Verify device cleanup in impl_state_free()
    
    We free it in the task function, so it's already NULL when freeing the
    state struct. Change the redudant unref to a NULL check warning.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1688>

 src/backends/native/meta-virtual-input-device-native.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/backends/native/meta-virtual-input-device-native.c 
b/src/backends/native/meta-virtual-input-device-native.c
index e6d9f47dfc..d2d13748ab 100644
--- a/src/backends/native/meta-virtual-input-device-native.c
+++ b/src/backends/native/meta-virtual-input-device-native.c
@@ -1033,7 +1033,7 @@ meta_virtual_input_device_native_constructed (GObject *object)
 static void
 impl_state_free (ImplState *impl_state)
 {
-  g_clear_object (&impl_state->device);
+  g_warn_if_fail (!impl_state->device);
   g_free (impl_state);
 }