[gnome-music] Make the cancel button as center vertically

[Vadim Rutkovsky <vrutkovsky src gnome org>]

commit 62b8177b7261f8d57ca41b0451edb4d63f48c435
Author: Yosef Or Boczko <yoseforb gmail com>
Date:   Wed Sep 18 14:14:28 2013 +0300

    Make the cancel button as center vertically
    
    https://bugzilla.gnome.org/show_bug.cgi?id=708279

 data/headerbar.ui.in |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/data/headerbar.ui.in b/data/headerbar.ui.in
index 2dea0ca..f22a102 100644
--- a/data/headerbar.ui.in
+++ b/data/headerbar.ui.in
@@ -172,4 +172,11 @@
       </packing>
     </child>
   </object>
+  <object class="GtkSizeGroup" id="size1">
+      <property name="mode">vertical</property>
+      <widgets>
+        <widget name="search-button"/>
+        <widget name="done-button"/>
+      </widgets>
+  </object>
 </interface>