Merge MAGETWO-88654 into 2.3-bugfixes-031018

Author: dvoskoboinikov

app/code/Magento/SalesRule/Block/Adminhtml/Promo/Widget/Chooser.php

@@ -3,8 +3,12 @@
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
+
 namespace Magento\SalesRule\Block\Adminhtml\Promo\Widget;
 
+/**
+ * Widget that allows to select a sales rule.
+ */
 class Chooser extends \Magento\Backend\Block\Widget\Grid\Extended
 {
     /**
@@ -87,7 +91,7 @@ public function prepareElementHtml(\Magento\Framework\Data\Form\Element\Abstract
         if ($element->getValue()) {
             $rule = $this->ruleFactory->create()->load((int)$element->getValue());
             if ($rule->getId()) {
-                $chooser->setLabel($rule->getName());
+                $chooser->setLabel($this->escapeHtml($rule->getName()));
             }
         }