[Notifier] Fix SentMessage implementation

Author: fabpot

CHANGELOG.md

@@ -4,7 +4,7 @@ CHANGELOG
 5.2.0
 -----
 
- * [BC BREAK] The `TransportInterface::send()` and `AbstractTransport::doSend()` methods changed to return a `SentMessage` instance instead of `void`.
+ * [BC BREAK] The `TransportInterface::send()` and `AbstractTransport::doSend()` methods changed to return a `?SentMessage` instance instead of `void`.
 
 5.1.0
 -----

Chatter.php

@@ -48,16 +48,20 @@ public function supports(MessageInterface $message): bool
         return $this->transport->supports($message);
     }
 
-    public function send(MessageInterface $message): SentMessage
+    public function send(MessageInterface $message): ?SentMessage
     {
         if (null === $this->bus) {
-            return $this->transport->send($message);
+            $this->transport->send($message);
+
+            return null;
         }
 
         if (null !== $this->dispatcher) {
             $this->dispatcher->dispatch(new MessageEvent($message, true));
         }
 
         $this->bus->dispatch($message);
+
+        return null;
     }
 }

Texter.php

@@ -48,16 +48,20 @@ public function supports(MessageInterface $message): bool
         return $this->transport->supports($message);
     }
 
-    public function send(MessageInterface $message): SentMessage
+    public function send(MessageInterface $message): ?SentMessage
     {
         if (null === $this->bus) {
-            return $this->transport->send($message);
+            $this->transport->send($message);
+
+            return null;
         }
 
         if (null !== $this->dispatcher) {
             $this->dispatcher->dispatch(new MessageEvent($message, true));
         }
 
         $this->bus->dispatch($message);
+
+        return null;
     }
 }

Transport/TransportInterface.php

@@ -25,7 +25,7 @@ interface TransportInterface
     /**
      * @throws TransportExceptionInterface
      */
-    public function send(MessageInterface $message): SentMessage;
+    public function send(MessageInterface $message): ?SentMessage;
 
     public function supports(MessageInterface $message): bool;