Rework polyfills loading (#24907)

app/javascript/mastodon/polyfills/base_polyfills.ts

@@ -1,26 +1,16 @@
 import 'intl';
 import 'intl/locale-data/jsonp/en';
-import 'es6-symbol/implement';
-import assign from 'object-assign';
-import values from 'object.values';
-import { decode as decodeBase64 } from './utils/base64';
-import promiseFinally from 'promise.prototype.finally';
-
-if (!Object.assign) {
-  Object.assign = assign;
-}
-
-if (!Object.values) {
-  values.shim();
-}
-
-promiseFinally.shim();
+import 'core-js/features/object/assign';
+import 'core-js/features/object/values';
+import 'core-js/features/symbol';
+import 'core-js/features/promise/finally';
+import { decode as decodeBase64 } from '../utils/base64';
 
 if (!HTMLCanvasElement.prototype.toBlob) {
   const BASE64_MARKER = ';base64,';
 
   Object.defineProperty(HTMLCanvasElement.prototype, 'toBlob', {
-    value(callback, type = 'image/png', quality) {
+    value(callback: BlobCallback, type = 'image/png', quality: any)  {
       const dataURL = this.toDataURL(type, quality);
       let data;
 

app/javascript/mastodon/polyfills/index.ts

@@ -10,14 +10,14 @@ function importExtraPolyfills() {
   return import(/* webpackChunkName: "extra_polyfills" */ './extra_polyfills');
 }
 
-function loadPolyfills() {
+export function loadPolyfills() {
   const needsBasePolyfills = !(
-    HTMLCanvasElement.prototype.toBlob &&
-    window.Intl &&
-    Object.assign &&
-    Object.values &&
-    window.Symbol &&
-    Promise.prototype.finally
+    'toBlob' in HTMLCanvasElement.prototype &&
+    'Intl' in window &&
+    'assign' in Object &&
+    'values' in Object &&
+    'Symbol' in window &&
+    'finally' in Promise.prototype
   );
 
   // Latest version of Firefox and Safari do not have IntersectionObserver.
@@ -36,5 +36,3 @@ function loadPolyfills() {
     needsExtraPolyfills && importExtraPolyfills(),
   ]);
 }
-
-export default loadPolyfills;

app/javascript/packs/application.js

@@ -1,5 +1,5 @@
 import './public-path';
-import loadPolyfills from '../mastodon/load_polyfills';
+import { loadPolyfills } from '../mastodon/polyfills';
 import { start } from '../mastodon/common';
 
 start();

app/javascript/packs/public.jsx

@@ -1,9 +1,9 @@
 import './public-path';
-import loadPolyfills from '../mastodon/load_polyfills';
+import escapeTextContentForBrowser from 'escape-html';
+import { loadPolyfills } from '../mastodon/polyfills';
+import ready from '../mastodon/ready';
 import { start } from '../mastodon/common';
 
-import escapeTextContentForBrowser from 'escape-html';
-import ready from '../mastodon/ready';
 import loadKeyboardExtensions from '../mastodon/load_keyboard_extensions';
 import 'cocoon-js-vanilla';
 import axios from 'axios';

app/javascript/packs/share.jsx

@@ -1,5 +1,5 @@
 import './public-path';
-import loadPolyfills from '../mastodon/load_polyfills';
+import { loadPolyfills } from '../mastodon/polyfills';
 import { start } from '../mastodon/common';
 import ready from '../mastodon/ready';
 import ComposeContainer  from '../mastodon/containers/compose_container';