[Notifier] Return SentMessage from the Notifier message handler

Author: fabpot

Messenger/MessageHandler.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\Notifier\Messenger;
 
 use Symfony\Component\Notifier\Message\MessageInterface;
+use Symfony\Component\Notifier\Message\SentMessage;
 use Symfony\Component\Notifier\Transport\TransportInterface;
 
 /**
@@ -28,8 +29,8 @@ public function __construct(TransportInterface $transport)
         $this->transport = $transport;
     }
 
-    public function __invoke(MessageInterface $message)
+    public function __invoke(MessageInterface $message): ?SentMessage
     {
-        $this->transport->send($message);
+        return $this->transport->send($message);
     }
 }