[gtk] fixup: warn about nothing events

[Matthias Clasen <matthiasc src gnome org>]

commit b82e57fec6691c130ef9e9b5b3f06880ee1af534
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Feb 23 21:24:00 2019 -0500

    fixup: warn about nothing events

 gdk/gdkevents.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/gdk/gdkevents.c b/gdk/gdkevents.c
index a076da7b7b..3b0944d3cc 100644
--- a/gdk/gdkevents.c
+++ b/gdk/gdkevents.c
@@ -150,7 +150,10 @@ void
 _gdk_event_emit (GdkEvent *event)
 {
   if (gdk_event_get_event_type (event) == GDK_NOTHING)
-    return;
+    {
+      g_warning ("Ignoring GDK_NOTHING events; they're good for nothing");
+      return;
+    }
 
   if (gdk_drag_handle_source_event (event))
     return;