fix: make babel-polyfill working

see gatsbyjs/gatsby#2177

gatsby-browser.ts

@@ -0,0 +1,26 @@
+/**
+ * *** CONFIDENTIAL ***
+ * -------------------------------------------------------------------------
+ * Unauthorized copying of this file, via any medium is strictly prohibited.
+ * -------------------------------------------------------------------------
+ *
+ * @summary The following script defines actions to
+ * be loaded in the clients' browser.
+ *
+ * @author Alvis HT Tang <alvis@hilbert.space>
+ * @license Proprietary
+ * @copyright Copyright (c) 2018 - All Rights Reserved.
+ * -------------------------------------------------------------------------
+ */
+
+import 'babel-polyfill';
+import Browser from '#definitions/gatsby/browser';
+
+/*
+ * onClientEntry is required for the polyfill to be loaded
+ * see https://github.com/gatsbyjs/gatsby/issues/2177
+ */
+export const onClientEntry: Browser.onClientEntry = () => {
+ // Don't need to do anything here, but if you don't
+ // export something, the import won't work.
+};