Issue #2778445 by neclimdul, anish.a, Charlotte17, arturs.v, iMiksu, heddn,...

Issue #2778445 by neclimdul, anish.a, Charlotte17, arturs.v, iMiksu, heddn, mikeryan: Add migration message property to migrate executable

core/modules/migrate/src/MigrateExecutable.php

@@ -94,6 +94,15 @@ class MigrateExecutable implements MigrateExecutableInterface {
    */
   protected $eventDispatcher;
 
+  /**
+   * Migration message service.
+   *
+   * @todo https://www.drupal.org/node/2822663 Make this protected.
+   *
+   * @var \Drupal\migrate\MigrateMessageInterface
+   */
+  public $message;
+
   /**
    * Constructs a MigrateExecutable and verifies and sets the memory limit.
    *