[orca] Create a Thunderbird-specific onChildrenChanged callback

[Joanmarie Diggs <joanied src gnome org>]

commit f8027cce9b13e37d991412d5fe500794c644eabe
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Mon Jan 27 05:39:49 2014 -0500

    Create a Thunderbird-specific onChildrenChanged callback

 src/orca/scripts/apps/Thunderbird/script.py |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/src/orca/scripts/apps/Thunderbird/script.py b/src/orca/scripts/apps/Thunderbird/script.py
index 3d0a58b..a758f81 100644
--- a/src/orca/scripts/apps/Thunderbird/script.py
+++ b/src/orca/scripts/apps/Thunderbird/script.py
@@ -154,6 +154,11 @@ class Script(Gecko.Script):
                 self.speakMessage(obj.name)
                 self._presentMessage(obj)
 
+    def onChildrenChanged(self, event):
+        """Callback for object:children-changed accessibility events."""
+
+        default.Script.onChildrenChanged(self, event)
+
     def onShowingChanged(self, event):
         """Callback for object:state-changed:showing accessibility events."""