Fix notifications

src/Core/Notifications/Commands/ReadNotificationHandler.php

@@ -6,8 +6,6 @@ use Flarum\Core\Support\DispatchesEvents;
 
 class ReadNotificationHandler
 {
-    use DispatchesEvents;
-
     /**
      * @param ReadNotification $command
      * @return Notification
@@ -26,8 +24,6 @@ class ReadNotificationHandler
         $notification->read();
         $notification->save();
 
-        $this->dispatchEventsFor($notification);
-
         return $notification;
     }
 }

src/Core/Notifications/DiscussionRenamedBlueprint.php

@@ -54,6 +54,6 @@ class DiscussionRenamedBlueprint implements Blueprint
      */
     public static function getSubjectModel()
     {
-        return 'Flarum\Core\Models\Discussion';
+        return 'Flarum\Core\Discussions\Discussion';
     }
 }

src/Core/Notifications/Notification.php

@@ -1,6 +1,7 @@
 <?php namespace Flarum\Core\Notifications;
 
 use Flarum\Core\Model;
+use Flarum\Core\Support\MappedMorphToTrait;
 
 /**
  * Models a notification record in the database.
@@ -20,6 +21,8 @@ use Flarum\Core\Model;
  */
 class Notification extends Model
 {
+    use MappedMorphToTrait;
+
     /**
      * {@inheritdoc}
      */
@@ -111,7 +114,7 @@ class Notification extends Model
      */
     public function subject()
     {
-        return $this->morphTo('subject', 'subjectModel', 'subject_id');
+        return $this->mappedMorphTo(static::$subjectModels, 'subject', 'type', 'subject_id');
     }
 
     /**