mash: Introduce WmSystemTrayNotifier for //ash/common

ash/system/tray_update.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_update.h"
 
 #include "ash/common/system/tray/fixed_sized_image_view.h"
 #include "ash/common/system/tray/system_tray_delegate.h"
 #include "ash/common/system/tray/tray_constants.h"
+#include "ash/common/system/tray/wm_system_tray_notifier.h"
 #include "ash/common/wm_shell.h"
-#include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
-#include "ash/system/tray/system_tray_notifier.h"
 #include "grit/ash_resources.h"
 #include "grit/ash_strings.h"
 #include "ui/aura/window.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/image/image.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/widget/widget.h"
 
@@ skipping 58 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(UpdateView);
 };
 
 }
 
 namespace ash {
 
 TrayUpdate::TrayUpdate(SystemTray* system_tray)
     : TrayImageItem(system_tray, IDR_AURA_UBER_TRAY_UPDATE) {
-  Shell::GetInstance()->system_tray_notifier()->AddUpdateObserver(this);
+  WmShell::Get()->system_tray_notifier()->AddUpdateObserver(this);
 }
 
 TrayUpdate::~TrayUpdate() {
-  Shell::GetInstance()->system_tray_notifier()->RemoveUpdateObserver(this);
+  WmShell::Get()->system_tray_notifier()->RemoveUpdateObserver(this);
 }
 
 bool TrayUpdate::GetInitialVisibility() {
   UpdateInfo info;
   WmShell::Get()->system_tray_delegate()->GetSystemUpdateInfo(&info);
   return info.update_required;
 }
 
 views::View* TrayUpdate::CreateDefaultView(LoginStatus status) {
   UpdateInfo info;
   WmShell::Get()->system_tray_delegate()->GetSystemUpdateInfo(&info);
   return info.update_required ? new UpdateView(info) : nullptr;
 }
 
 void TrayUpdate::OnUpdateRecommended(const UpdateInfo& info) {
   SetImageFromResourceId(DecideResource(info.severity, false));
   tray_view()->SetVisible(true);
 }
 
 }  // namespace ash