ash: Add a bluetooth entry in the uber tray.

ash/system/tray_accessibility.cc

 // 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.
 
 #include "ash/system/tray_accessibility.h"
 
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "grit/ui_resources.h"
 #include "ui/views/controls/image_view.h"
 
 namespace ash {
 namespace internal {
 
 TrayAccessibility::TrayAccessibility()
     : TrayImageItem(IDR_AURA_UBER_TRAY_ACCESSIBILITY) {
 }
 
 TrayAccessibility::~TrayAccessibility() {}
 
-bool TrayAccessibility::ShouldDisplay() {
+bool TrayAccessibility::InitialVisibility() {
   return ash::Shell::GetInstance()->tray_delegate()->IsInAccessibilityMode();
 }
 
 void TrayAccessibility::OnAccessibilityModeChanged(bool enabled) {
   if (image_view())
     image_view()->SetVisible(enabled);
 }
 
 }  // namespace internal
 }  // namespace ash