The trait and interface didn't matched

src/Revision/EntityRevisionLogInterface.php

@@ -6,6 +6,7 @@
  */
 
 namespace Drupal\entity\Revision;
+use Drupal\user\UserInterface;
 
 /**
  * Defines an entity type with create time/author/log information for revisions.
@@ -48,7 +49,7 @@ interface EntityRevisionLogInterface {
    *
    * @return $this
    */
-  public function setRevisionUser($account);
+  public function setRevisionUser(UserInterface $account);
 
   /**
    * Gets the entity revision author ID.