[gtk+/native-layout] Added an argument check to gtk_distribute_natural_allocation()

[Tristan Van Berkom <tvb src gnome org>]

commit 7d3cb3f9d9a73ffeb15737124bd545bae7ce0eaf
Author: Tristan Van Berkom <tristan van berkom gmail com>
Date:   Tue Aug 17 01:29:23 2010 -0400

    Added an argument check to gtk_distribute_natural_allocation()
    
    and clipped some values in gtkbox.c in case it was allocated less
    than it requested.

 gtk/gtkbox.c         |    4 ++--
 gtk/gtksizerequest.c |    2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkbox.c b/gtk/gtkbox.c
index cdc5f1d..1f9b637 100644
--- a/gtk/gtkbox.c
+++ b/gtk/gtkbox.c
@@ -500,7 +500,7 @@ gtk_box_size_allocate (GtkWidget     *widget,
   else
     {
       /* Bring children up to size first */
-      size = gtk_distribute_natural_allocation (size, nvis_children, sizes);
+      size = gtk_distribute_natural_allocation (MAX (0, size), nvis_children, sizes);
 
       /* Calculate space which hasn't distributed yet,
        * and is available for expanding children.
@@ -1004,7 +1004,7 @@ gtk_box_compute_size_for_opposing_orientation (GtkBox *box,
   else
     {
       /* Bring children up to size first */
-      size = gtk_distribute_natural_allocation (size, nvis_children, sizes);
+      size = gtk_distribute_natural_allocation (MAX (0, size), nvis_children, sizes);
 
       /* Calculate space which hasn't distributed yet,
        * and is available for expanding children.
diff --git a/gtk/gtksizerequest.c b/gtk/gtksizerequest.c
index 81c66f6..908cc39 100644
--- a/gtk/gtksizerequest.c
+++ b/gtk/gtksizerequest.c
@@ -584,6 +584,8 @@ gtk_distribute_natural_allocation (gint              extra_space,
   guint *spreading = g_newa (guint, n_requested_sizes);
   gint   i;
 
+  g_return_val_if_fail (extra_space >= 0, 0);
+
   for (i = 0; i < n_requested_sizes; i++)
     spreading[i] = i;