Only return the visible page actions from PageActionController.

chrome/common/chrome_notification_types.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_COMMON_CHROME_NOTIFICATION_TYPES_H_
 #define CHROME_COMMON_CHROME_NOTIFICATION_TYPES_H_
 #pragma once
 
 #include "content/public/browser/notification_types.h"
 
@@ skipping 412 matching lines @@
 
   // Sent when a CrxInstaller finishes. Source is the CrxInstaller that
   // finished.  No details.
   NOTIFICATION_CRX_INSTALLER_DONE,
 
   // Sent when the known installed extensions have all been loaded.  In
   // testing scenarios this can happen multiple times if extensions are
   // unloaded and reloaded. The source is a Profile.
   NOTIFICATION_EXTENSIONS_READY,
 
+  // Sent when the extension action box is updated for a tab. The source is the
+  // Profile and the details are the TabContentsWrapper for the tab.
+  NOTIFICATION_EXTENSION_ACTION_BOX_UPDATED,
+
   // Sent when a new extension is loaded. The details are an Extension, and
   // the source is a Profile.
   NOTIFICATION_EXTENSION_LOADED,
 
   // An error occured while attempting to load an extension. The details are a
   // string with details about why the load failed.
   NOTIFICATION_EXTENSION_LOAD_ERROR,
 
   // Sent when attempting to load a new extension, but they are disabled. The
   // details are an Extension*, and the source is a Profile*.
@@ skipping 673 matching lines @@
   // Currently only Content and Chrome define and use notifications.
   // Custom notifications not belonging to Content and Chrome should start
   // from here.
   NOTIFICATION_CHROME_END,
 };
 
 }  // namespace chrome
 
 
 #endif  // CHROME_COMMON_CHROME_NOTIFICATION_TYPES_H_