[gtk+] Fix separator in testsplitheaders

[Matthias Clasen <matthiasc src gnome org>]

commit 505fed1383fc3f092f8ee1f9d2f1f840f8579953
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Mar 28 22:32:12 2015 -0400

    Fix separator in testsplitheaders

 tests/testsplitheaders.ui |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/tests/testsplitheaders.ui b/tests/testsplitheaders.ui
index ca68311..66bfe4e 100644
--- a/tests/testsplitheaders.ui
+++ b/tests/testsplitheaders.ui
@@ -24,6 +24,7 @@
         <child>
           <object class="GtkSeparator">
             <property name="visible">True</property>
+            <property name="orientation">vertical</property>
           </object>
         </child>
         <child>