mostly finished rewrite

public/node_modules/dom-helpers/cjs/ownerDocument.js

@@ -0,0 +1,15 @@
+"use strict";
+
+exports.__esModule = true;
+exports.default = ownerDocument;
+
+/**
+ * Returns the owner document of a given element.
+ * 
+ * @param node the element
+ */
+function ownerDocument(node) {
+  return node && node.ownerDocument || document;
+}
+
+module.exports = exports["default"];