Filepicker breadcrumb null=>undefined #1368

Author: FredrikEkstroem

src/controls/filePicker/SiteFilePickerTab/SiteFilePickerTab.tsx

@@ -209,21 +209,21 @@ export default class SiteFilePickerTab extends React.Component<ISiteFilePickerTa
     let { breadcrumbItems } = this.state;
     let breadcrumbClickedItemIndx = 0;
     // Site node clicked
-    if (node.libraryData === null && node.folderData === null) {
+    if (node.libraryData === undefined && node.folderData === undefined) {
       this.setState({
         libraryAbsolutePath: undefined,
         libraryPath: undefined,
         folderName: undefined
       });
     }
     // Check if it is folder item
-    else if (node.folderData !== null) {
+    else if (node.folderData !== undefined) {
       this._handleOpenFolder(node.folderData, false);
       // select which node has been clicked
       breadcrumbClickedItemIndx = findIndex(breadcrumbItems, item => item.folderData && item.folderData.absoluteUrl === node.key);
     }
     // Check if it is library node
-    else if (node.libraryData !== null) {
+    else if (node.libraryData !== undefined) {
       this._handleOpenLibrary(node.libraryData, false);
       // select which node has been clicked
       breadcrumbClickedItemIndx = findIndex(breadcrumbItems, item => item.libraryData && item.libraryData.serverRelativeUrl === node.key);