[gtk/wip/baedert/transforms6: 257/273] compute_bounds: Add preconditions

[Timm Bäder <baedert src gnome org>]

commit e7e6e7c99a581b6627b4111d41f7eeebcf011754
Author: Timm Bäder <mail baedert org>
Date:   Sat Aug 18 14:47:08 2018 +0200

    compute_bounds: Add preconditions

 gtk/gtkwidget.c | 4 ++++
 1 file changed, 4 insertions(+)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 8154cc3b7c..6ee4af4234 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -11308,6 +11308,10 @@ gtk_widget_compute_bounds (GtkWidget       *widget,
   GtkCssStyle *style;
   GtkBorder margin, border, padding;
 
+  g_return_val_if_fail (GTK_IS_WIDGET (widget), FALSE);
+  g_return_val_if_fail (GTK_IS_WIDGET (target), FALSE);
+  g_return_val_if_fail (out_bounds != NULL, FALSE);
+
   ancestor = gtk_widget_common_ancestor (widget, target);
 
   if (!ancestor)