Promotes more accessors from WmShell to Shell

ash/common/system/date/tray_date.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/common/system/date/tray_date.h"
 
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/system/chromeos/system_clock_observer.h"
 #include "ash/common/system/date/date_default_view.h"
 #include "ash/common/system/date/date_view.h"
 #include "ash/common/system/tray/system_tray.h"
 #include "ash/common/system/tray/system_tray_notifier.h"
 #include "ash/common/system/tray/tray_item_view.h"
-#include "ash/common/wm_shell.h"
+#include "ash/shell.h"
 
 namespace ash {
 
 TrayDate::TrayDate(SystemTray* system_tray)
     : SystemTrayItem(system_tray, UMA_DATE),
       time_tray_(NULL),
       default_view_(NULL),
       login_status_(LoginStatus::NOT_LOGGED_IN),
       system_clock_observer_(new SystemClockObserver()) {
-  WmShell::Get()->system_tray_notifier()->AddClockObserver(this);
+  Shell::Get()->system_tray_notifier()->AddClockObserver(this);
 }
 
 TrayDate::~TrayDate() {
-  WmShell::Get()->system_tray_notifier()->RemoveClockObserver(this);
+  Shell::Get()->system_tray_notifier()->RemoveClockObserver(this);
 }
 
 views::View* TrayDate::GetHelpButtonView() const {
   if (!default_view_)
     return NULL;
   return default_view_->GetHelpButtonView();
 }
 
 const tray::TimeView* TrayDate::GetTimeTrayForTesting() const {
   return time_tray_;
@@ skipping 78 matching lines @@
                      : tray::DateView::DateAction::NONE);
   }
 }
 
 void TrayDate::Refresh() {
   if (time_tray_)
     time_tray_->UpdateText();
 }
 
 }  // namespace ash