Expose serializer/actor to extensions

src/Api/Serializers/BaseSerializer.php

@@ -11,7 +11,7 @@ use Closure;
  */
 abstract class BaseSerializer extends SerializerAbstract
 {
-    protected $actor;
+    public $actor;
 
     /**
      * The custom relationships on this serializer.

src/Support/ServiceProvider.php

@@ -87,7 +87,7 @@ class ServiceProvider extends IlluminateServiceProvider
     {
         $this->app['events']->listen('Flarum\Api\Events\SerializeAttributes', function ($event) use ($serializer, $callback) {
             if ($event->serializer instanceof $serializer) {
-                $callback($event->attributes, $event->model);
+                $callback($event->attributes, $event->model, $event->serializer);
             }
         });
     }