Move more from WmShell to Shell

ash/common/system/date/date_default_view.cc

 // Copyright 2014 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/date_default_view.h"
 
 #include "ash/common/metrics/user_metrics_action.h"
 #include "ash/common/session/session_controller.h"
 #include "ash/common/shutdown_controller.h"
 #include "ash/common/system/date/date_view.h"
@@ skipping 110 matching lines @@
 
 const tray::DateView* DateDefaultView::GetDateView() const {
   return date_view_;
 }
 
 void DateDefaultView::ButtonPressed(views::Button* sender,
                                     const ui::Event& event) {
   WmShell* shell = WmShell::Get();
   if (sender == help_button_) {
     shell->RecordUserMetricsAction(UMA_TRAY_HELP);
-    shell->system_tray_controller()->ShowHelp();
+    Shell::Get()->system_tray_controller()->ShowHelp();
   } else if (sender == shutdown_button_) {
     shell->RecordUserMetricsAction(UMA_TRAY_SHUT_DOWN);
     Shell::GetInstance()->lock_state_controller()->RequestShutdown();
   } else if (sender == lock_button_) {
     shell->RecordUserMetricsAction(UMA_TRAY_LOCK_SCREEN);
     chromeos::DBusThreadManager::Get()
         ->GetSessionManagerClient()
         ->RequestLockScreen();
   } else {
     NOTREACHED();
   }
   date_view_->CloseSystemBubble();
 }
 
 }  // namespace ash