Backport #30723

Move babel whitelist helpers to a common file

build/rollup.config.js

@@ -4,6 +4,7 @@ const path    = require('path')
 const babel   = require('rollup-plugin-babel')
 const resolve = require('@rollup/plugin-node-resolve')
 const banner  = require('./banner.js')
+const babelHelpers = require('./babel-helpers.js')
 
 const BUNDLE  = process.env.BUNDLE === 'true'
 
@@ -11,15 +12,10 @@ let fileDest  = 'bootstrap.js'
 const external = ['jquery', 'popper.js']
 const plugins = [
   babel({
-    exclude: 'node_modules/**', // Only transpile our source code
-    externalHelpersWhitelist: [ // Include only required helpers
-      'defineProperties',
-      'createClass',
-      'createSuper',
-      'inheritsLoose',
-      'defineProperty',
-      'objectSpread2'
-    ]
+  // Only transpile our source code
+    exclude: 'node_modules/**',
+    // Include only required helpers
+    externalHelpersWhitelist: babelHelpers
   })
 ]
 const globals = {