Destroy SystemTrayDelegate in Shutdown()

ash/system/status_area_widget.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/status_area_widget.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_window_ids.h"
@@ skipping 287 matching lines @@
 
 void StatusAreaWidget::CreateTrayViews(ShellDelegate* shell_delegate) {
   AddWebNotificationTray(new WebNotificationTray(this));
   AddSystemTray(new SystemTray(this), shell_delegate);
 }
 
 void StatusAreaWidget::Shutdown() {
   // Destroy the trays early, causing them to be removed from the view
   // hierarchy. Do not used scoped pointers since we don't want to destroy them
   // in the destructor if Shutdown() is not called (e.g. in tests).
+  system_tray_delegate_.reset();
   delete system_tray_;
   system_tray_ = NULL;
   delete web_notification_tray_;
   web_notification_tray_ = NULL;
 }
 
 void StatusAreaWidget::AddSystemTray(SystemTray* system_tray,
                                      ShellDelegate* shell_delegate) {
   system_tray_ = system_tray;
   widget_delegate_->AddTray(system_tray);
@@ skipping 51 matching lines @@
     user::LoginStatus login_status) {
   login_status_ = login_status;
   if (system_tray_)
     system_tray_->UpdateAfterLoginStatusChange(login_status);
   if (web_notification_tray_)
     web_notification_tray_->UpdateAfterLoginStatusChange(login_status);
 }
 
 }  // namespace internal
 }  // namespace ash