Add supporting themes required for Lotusdocs

themes/hugo-mod-jslibs-dist/popperjs/package/lib/dom-utils/getScrollParent.js.flow

@@ -0,0 +1,18 @@
+// @flow
+import getParentNode from './getParentNode';
+import isScrollParent from './isScrollParent';
+import getNodeName from './getNodeName';
+import { isHTMLElement } from './instanceOf';
+
+export default function getScrollParent(node: Node): HTMLElement {
+  if (['html', 'body', '#document'].indexOf(getNodeName(node)) >= 0) {
+    // $FlowFixMe[incompatible-return]: assume body is always available
+    return node.ownerDocument.body;
+  }
+
+  if (isHTMLElement(node) && isScrollParent(node)) {
+    return node;
+  }
+
+  return getScrollParent(getParentNode(node));
+}