[gtk: 1/2] gtk/gtktooltip.c: check result of event position get operation

[Matthias Clasen <matthiasc src gnome org>]

commit 982b4ff3b22aee04e5f91c04e95a6c6b9d8b66e2
Author: Maxim Zakharov <zakhma muli com au>
Date:   Tue Aug 30 15:45:52 2022 +1000

    gtk/gtktooltip.c: check result of event position get operation
    
    Do not perform coordinates transformation when gdk_event_get_position()
    returns FALSE as it returns NaNs in that case and these coordinates
    are not used anyway in further processing (closes #5134).

 gtk/gtktooltip.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)
---
diff --git a/gtk/gtktooltip.c b/gtk/gtktooltip.c
index 9f0fa15cca..54708a14aa 100644
--- a/gtk/gtktooltip.c
+++ b/gtk/gtktooltip.c
@@ -925,16 +925,18 @@ _gtk_tooltip_handle_event (GtkWidget *target,
     return;
 
   event_type = gdk_event_get_event_type (event);
-  surface = gdk_event_get_surface (event);
-  gdk_event_get_position (event, &x, &y);
 
   /* ignore synthetic motion events */
   if (event_type == GDK_MOTION_NOTIFY &&
       gdk_event_get_time (event) == GDK_CURRENT_TIME)
     return;
 
-  gtk_native_get_surface_transform (native, &nx, &ny);
-  gtk_widget_translate_coordinates (GTK_WIDGET (native), target, x - nx, y - ny, &x, &y);
+  surface = gdk_event_get_surface (event);
+  if (gdk_event_get_position (event, &x, &y))
+    {
+      gtk_native_get_surface_transform (native, &nx, &ny);
+      gtk_widget_translate_coordinates (GTK_WIDGET (native), target, x - nx, y - ny, &x, &y);
+    }
   gtk_tooltip_handle_event_internal (event_type, surface, target, x, y);
 }