Merge ArcNotificationItem and ArcCustomNotificationItem

ui/arc/notification/arc_notification_manager.cc

Index: ui/arc/notification/arc_notification_manager.cc
diff --git a/ui/arc/notification/arc_notification_manager.cc b/ui/arc/notification/arc_notification_manager.cc
index 7f63ba2a09656ee76f3274fd1a820b3d21f46c6f..3fedf98a589fd1ba4471a31422e7b2ab3953574b 100644
--- a/ui/arc/notification/arc_notification_manager.cc
+++ b/ui/arc/notification/arc_notification_manager.cc
@@ -13,8 +13,7 @@
 #include "base/stl_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/arc/arc_bridge_service.h"
-#include "ui/arc/notification/arc_custom_notification_item.h"
-#include "ui/arc/notification/arc_notification_item.h"
+#include "ui/arc/notification/arc_notification_item_impl.h"
 
 namespace arc {
 
@@ -66,19 +65,12 @@ void ArcNotificationManager::OnNotificationPosted(
   const std::string& key = data->key;
   auto it = items_.find(key);
   if (it == items_.end()) {
-    // Old client with version < 5 would have use_custom_notification default,
-    // which is false.
-    const bool use_custom_notification = data->use_custom_notification;
     // Show a notification on the primary logged-in user's desktop.
     // TODO(yoshiki): Reconsider when ARC supports multi-user.
-    ArcNotificationItem* item =
-        use_custom_notification
-            ? new ArcCustomNotificationItem(this, message_center_, key,
-                                            main_profile_id_)
-            : new ArcNotificationItem(this, message_center_, key,
-                                      main_profile_id_);
+    auto item = base::MakeUnique<ArcNotificationItemImpl>(
+        this, message_center_, key, main_profile_id_);
     // TODO(yoshiki): Use emplacement for performance when it's available.
-    auto result = items_.insert(std::make_pair(key, base::WrapUnique(item)));
+    auto result = items_.insert(std::make_pair(key, std::move(item)));
     DCHECK(result.second);
     it = result.first;
   }