add permission for voting on own content

Closes #3514730

src/Plugin/VotingApiWidgetBase.php

@@ -179,6 +179,9 @@ abstract class VotingApiWidgetBase extends PluginBase implements VotingApiWidget
     if (!$vote->isNew()) {
       $perm = 'edit own vote on ' . $vote->getVotedEntityType() . ':' . $entity->bundle() . ':' . $vote->field_name->value;
     }
+    if ($account->id() && $entity->getOwnerId() == $account->id()) {
+      $perm = 'vote on own ' . $vote->getVotedEntityType() . ':' . $entity->bundle() . ':' . $vote->field_name->value;
+    }
     return $account->hasPermission($perm);
   }