[orca] Fix for nameless panels delaying presentation of Top Bar button in gnome-shell

[Joanmarie Diggs <joanied src gnome org>]

commit 1296a29d00fe27d448b6c662f8223d8e0e530e8f
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Fri Apr 13 13:20:13 2012 -0400

    Fix for nameless panels delaying presentation of Top Bar button in gnome-shell

 src/orca/scripts/toolkits/CALLY/script.py |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)
---
diff --git a/src/orca/scripts/toolkits/CALLY/script.py b/src/orca/scripts/toolkits/CALLY/script.py
index 098ad44..fc27b7f 100644
--- a/src/orca/scripts/toolkits/CALLY/script.py
+++ b/src/orca/scripts/toolkits/CALLY/script.py
@@ -192,6 +192,21 @@ class Script(default.Script):
         - event: the Event
         """
 
+        # When entering overview with many open windows, we get quite
+        # a few state-changed:showing events for nameless panels. The
+        # act of processing these by the default script causes us to
+        # present nothing, and introduces a significant delay before
+        # presenting the Top Bar button when Ctrl+Alt+Tab was pressed.
+        if event.type.startswith("object:state-changed:showing"):
+            try:
+                role = event.source.getRole()
+                name = event.source.name
+            except:
+                pass
+            else:
+                if role == pyatspi.ROLE_PANEL and not name:
+                    return
+
         # We override the behaviour for the selection
         if event.type.startswith("object:state-changed:selected") \
            and event.detail1: