Remove some uses of stl_util's STLDeleteContainerPointers.

ui/message_center/notification_list_unittest.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 "ui/message_center/notification_list.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 70 matching lines @@
 
   NotificationList::PopupNotifications GetPopups() {
     return notification_list()->GetPopupNotifications(blockers_, NULL);
   }
 
   size_t GetPopupCounts() {
     return GetPopups().size();
   }
 
   Notification* GetNotification(const std::string& id) {
-    NotificationList::Notifications::iterator iter =
-        notification_list()->GetNotification(id);
+    auto iter = notification_list()->GetNotification(id);
     if (iter == notification_list()->notifications_.end())
       return NULL;
-    return *iter;
+    return iter->get();
   }
 
   NotificationList* notification_list() { return notification_list_.get(); }
   const NotificationBlockers& blockers() const { return blockers_; }
 
   static const char kIdFormat[];
   static const char kTitleFormat[];
   static const char kMessageFormat[];
   static const char kDisplaySource[];
   static const char kExtensionId[];
@@ skipping 556 matching lines @@
       NotifierId(), RichNotificationData(), NULL));
   notification_list()->AddNotification(std::move(updated_notification));
 
   EXPECT_FALSE(notification_list()->HasNotificationOfType(
       id, message_center::NOTIFICATION_TYPE_SIMPLE));
   EXPECT_TRUE(notification_list()->HasNotificationOfType(
       id, message_center::NOTIFICATION_TYPE_PROGRESS));
 }
 
 }  // namespace message_center