[gtk/wip/otte/listview: 134/149] widget: Add a hook for resizes

[Benjamin Otte <otte src gnome org>]

commit 6992dd94438a1a06bf1f5da5f63f1c2f41a8bdf6
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 21587a511d..39d2e60e50 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -4110,6 +4110,9 @@ 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 68595f7aa9..ff602ee5e9 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 */