Add accessible names to buttons in the Uber tray

ash/system/bluetooth/tray_bluetooth.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/bluetooth/tray_bluetooth.h"
 
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "ash/system/tray/tray_constants.h"
@@ skipping 81 matching lines @@
     if (login_ == user::LOGGED_IN_LOCKED)
       return;
 
     // Do not allow toggling bluetooth in the lock screen.
     ash::SystemTrayDelegate* delegate =
         ash::Shell::GetInstance()->tray_delegate();
     toggle_bluetooth_ = new TrayPopupHeaderButton(this,
         IDR_AURA_UBER_TRAY_BLUETOOTH_ENABLED,
         IDR_AURA_UBER_TRAY_BLUETOOTH_DISABLED,
         IDR_AURA_UBER_TRAY_BLUETOOTH_ENABLED_HOVER,
-        IDR_AURA_UBER_TRAY_BLUETOOTH_DISABLED_HOVER);
+        IDR_AURA_UBER_TRAY_BLUETOOTH_DISABLED_HOVER,
+        IDS_ASH_STATUS_TRAY_BLUETOOTH);
     toggle_bluetooth_->SetToggled(!delegate->GetBluetoothEnabled());
     footer()->AddButton(toggle_bluetooth_);
   }
 
   void AppendDeviceList(const BluetoothDeviceList& list) {
     device_map_.clear();
     CreateScrollableList();
 
     for (size_t i = 0; i < list.size(); i++) {
       HoverHighlightView* container = new HoverHighlightView(this);
@@ skipping 110 matching lines @@
   BluetoothDeviceList list;
   Shell::GetInstance()->tray_delegate()->GetAvailableBluetoothDevices(&list);
   if (default_)
     default_->UpdateLabel();
   else if (detailed_)
     detailed_->Update(list);
 }
 
 }  // namespace internal
 }  // namespace ash