[meld] diffgrid: Support RTL layout flipping for DiffGrid

[Kai Willadsen <kaiw src gnome org>]

commit 576de3da63333d76fa70fd9c60348ce849ca2287
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Tue Oct 28 06:10:38 2014 +1000

    diffgrid: Support RTL layout flipping for DiffGrid

 meld/diffgrid.py |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/meld/diffgrid.py b/meld/diffgrid.py
index a836097..8495741 100644
--- a/meld/diffgrid.py
+++ b/meld/diffgrid.py
@@ -191,6 +191,12 @@ class DiffGrid(Gtk.Grid):
             child_alloc.y = yrows[top]
             child_alloc.width = columns[left + width] - columns[left]
             child_alloc.height = yrows[top + height] - yrows[top]
+
+            if self.get_direction() == Gtk.TextDirection.RTL:
+                child_alloc.x = (
+                    allocation.x + allocation.width -
+                    (child_alloc.x - allocation.x) - child_alloc.width)
+
             child.size_allocate(child_alloc)
 
         for child in self.get_children():