Issue #2825088 by kasperg: Migration property not defined in...

Issue #2825088 by kasperg: Migration property not defined in Drupal\migrate\Plugin\migrate\process\Migration

core/modules/migrate/src/Plugin/migrate/process/Migration.php

@@ -38,6 +38,13 @@ class Migration extends ProcessPluginBase implements ContainerFactoryPluginInter
    */
   protected $migrationPluginManager;
 
+  /**
+   * The migration to be executed.
+   *
+   * @var \Drupal\migrate\Plugin\MigrationInterface
+   */
+  protected $migration;
+
   /**
    * {@inheritdoc}
    */