chromeos: Move device shutdown handling out of chrome into ash

ash/common/system/tiles/tray_tiles.cc

 // Copyright 2016 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/common/system/tiles/tray_tiles.h"
 
 #include "ash/common/metrics/user_metrics_action.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/system/tiles/tiles_default_view.h"
 #include "ash/common/wm_shell.h"
 
 namespace ash {
 
 TrayTiles::TrayTiles(SystemTray* system_tray)
     : SystemTrayItem(system_tray, UMA_NOT_RECORDED), default_view_(nullptr) {}
 
 TrayTiles::~TrayTiles() {}
 
 views::View* TrayTiles::GetHelpButtonView() const {
   if (!default_view_)
     return nullptr;
   return default_view_->GetHelpButtonView();
 }
 
+TilesDefaultView* TrayTiles::GetDefaultViewForTesting() const {
+  return default_view_;
+}
+
 views::View* TrayTiles::CreateDefaultViewForTesting(LoginStatus status) {
   return CreateDefaultView(status);
 }
 
 views::View* TrayTiles::CreateDefaultView(LoginStatus status) {
   CHECK(default_view_ == nullptr);
   default_view_ = new TilesDefaultView(this, status);
   default_view_->Init();
   return default_view_;
 }
 
 void TrayTiles::DestroyDefaultView() {
   default_view_ = nullptr;
 }
 
 }  // namespace ash