[gtk] widget: Mark compute functions as G_GNUC_WARN_UNUSED_RESULT

[Benjamin Otte <otte src gnome org>]

commit 02e856f62e9eee7796bdff9ba8d8a9bda31c60fc
Author: Benjamin Otte <otte redhat com>
Date:   Wed Feb 20 05:00:13 2019 +0100

    widget: Mark compute functions as G_GNUC_WARN_UNUSED_RESULT
    
    Lots of code does not error-check these functions, and when we add CSS
    transforms, they will start failing. And we want people to check that.

 gtk/gtkwidget.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/gtk/gtkwidget.h b/gtk/gtkwidget.h
index f57f64b5ee..5e1768e132 100644
--- a/gtk/gtkwidget.h
+++ b/gtk/gtkwidget.h
@@ -612,16 +612,16 @@ void                  gtk_widget_get_allocation         (GtkWidget     *widget,
 GDK_AVAILABLE_IN_ALL
 gboolean                gtk_widget_compute_transform            (GtkWidget              *widget,
                                                                  GtkWidget              *target,
-                                                                 graphene_matrix_t      *out_transform);
+                                                                 graphene_matrix_t      *out_transform) 
G_GNUC_WARN_UNUSED_RESULT;
 GDK_AVAILABLE_IN_ALL
 gboolean                gtk_widget_compute_bounds               (GtkWidget              *widget,
                                                                  GtkWidget              *target,
-                                                                 graphene_rect_t        *out_bounds);
+                                                                 graphene_rect_t        *out_bounds) 
G_GNUC_WARN_UNUSED_RESULT;
 GDK_AVAILABLE_IN_ALL
 gboolean                gtk_widget_compute_point                (GtkWidget              *widget,
                                                                  GtkWidget              *target,
                                                                  const graphene_point_t *point,
-                                                                 graphene_point_t       *out_point);
+                                                                 graphene_point_t       *out_point) 
G_GNUC_WARN_UNUSED_RESULT;
 
 GDK_AVAILABLE_IN_ALL
 int                   gtk_widget_get_width              (GtkWidget     *widget);