[gnome-builder] column-layout: reverse layout for RTL languages

[Christian Hergert <chergert src gnome org>]

commit 690f9f0d2c2f7299faffc7523fa94887761ce3ad
Author: Christian Hergert <chergert redhat com>
Date:   Mon Oct 10 15:35:24 2016 -0700

    column-layout: reverse layout for RTL languages
    
    Rather than make the layout more complex when under an RTL
    language, we can just flip things around right before we
    size allocate our children.
    
    This seems to be the minimal number of strokes to support
    RTL for this widget.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=772700

 contrib/egg/egg-column-layout.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/contrib/egg/egg-column-layout.c b/contrib/egg/egg-column-layout.c
index 7a3ebd2..dc8cb11 100644
--- a/contrib/egg/egg-column-layout.c
+++ b/contrib/egg/egg-column-layout.c
@@ -266,6 +266,22 @@ egg_column_layout_size_allocate (GtkWidget     *widget,
 
   egg_column_layout_layout (self, allocation->width, allocation->height, &tallest_column);
 
+  /*
+   * If we are on a RTL language, flip all our allocations around so
+   * we move from right to left. This is easier than adding all the
+   * complexity to directions during layout time.
+   */
+  if (GTK_TEXT_DIR_RTL == gtk_widget_get_direction (widget))
+    {
+      for (i = 0; i < priv->children->len; i++)
+        {
+          EggColumnLayoutChild *child;
+
+          child = &g_array_index (priv->children, EggColumnLayoutChild, i);
+          child->alloc.x = allocation->x + allocation->width - child->alloc.x - child->alloc.width;
+        }
+    }
+
   for (i = 0; i < priv->children->len; i++)
     {
       EggColumnLayoutChild *child;