PB-369: Integrate third party library to work with DOMDocument

 - fix health failures

Author: cspruiell

app/code/Magento/PageBuilder/Model/Dom/Document.php

@@ -23,12 +23,12 @@ class Document implements DocumentInterface
     /**
      * @var ObjectManagerInterface
      */
-    protected $objectManager;
+    private $objectManager;
 
     /**
      * @var GtDomDocument
      */
-    protected $document;
+    private $document;
 
     /**
      * Document constructor.

app/code/Magento/PageBuilder/Model/Dom/HtmlDocument.php

@@ -18,6 +18,16 @@
  */
 class HtmlDocument extends Document implements HtmlDocumentInterface
 {
+    /**
+     * @var ObjectManagerInterface
+     */
+    private $objectManager;
+
+    /**
+     * @var GtDomHTMLDocument
+     */
+    private $document;
+
     /**
      * HtmlDocument constructor.
      * @param ObjectManagerInterface $objectManager

app/code/Magento/PageBuilder/Model/Dom/XmlDocument.php

@@ -16,6 +16,16 @@
  */
 class XmlDocument extends Document implements XmlDocumentInterface
 {
+    /**
+     * @var ObjectManagerInterface
+     */
+    private $objectManager;
+
+    /**
+     * @var GtDomXmlDocument
+     */
+    private $document;
+
     /**
      * XmlDocument constructor.
      *