[gtk/wip/otte/listview: 129/155] widget: Add a hook for resizes

[Benjamin Otte <otte src gnome org>]

commit e81f99e98edbff6fad94b398b4ad7d750ec69422
Author: Benjamin Otte <otte redhat com>
Date:   Tue Nov 5 00:40:17 2019 +0100

    widget: Add a hook for resizes
    
    It's private, no APIs, we don't talk about it. But we will start using
    it very soon, so we can do size request caching in columns and avoid
    sizegroups...

 gtk/gtkwidget.c        | 3 +++
 gtk/gtkwidgetprivate.h | 1 +
 2 files changed, 4 insertions(+)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 202efdb62d..982f36b1b2 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -3714,6 +3714,9 @@ gtk_widget_queue_resize_internal (GtkWidget *widget)
   priv->resize_needed = TRUE;
   gtk_widget_set_alloc_needed (widget);
 
+  if (priv->resize_func)
+    priv->resize_func (widget);
+
   groups = _gtk_widget_get_sizegroups (widget);
 
   for (l = groups; l; l = l->next)
diff --git a/gtk/gtkwidgetprivate.h b/gtk/gtkwidgetprivate.h
index 72fb1df993..6a6df7c076 100644
--- a/gtk/gtkwidgetprivate.h
+++ b/gtk/gtkwidgetprivate.h
@@ -122,6 +122,7 @@ struct _GtkWidgetPrivate
 
   int width_request;
   int height_request;
+  void (* resize_func) (GtkWidget *);
   GtkBorder margin;
 
   /* Animations and other things to update on clock ticks */