Add AfterCommitException

If a callback in commit throws an excecption, the calling plugin needs to be able to distinguish this from a unsuccessful commit, so that it doesn't attempt a rollback on an already commited transaction. (Which would cause an  “Asymmetric transaction rollback" error)

Author: waynetheisinger

lib/internal/Magento/Framework/Exception/AfterCommitException.php

@@ -0,0 +1,15 @@
+<?php
+/**
+ * AfterCommitException Exception
+ *
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Framework\Exception;
+
+/**
+ * @api
+ */
+class AfterCommitException extends \Exception
+{
+}