Polyfill Map and Set in React integration test

So that it works in IE10

test/endtoend/create-react-app/package-lock.json

@@ -2954,6 +2954,11 @@
         "event-emitter": "~0.3.5"
       }
     },
+    "es6-shim": {
+      "version": "0.35.3",
+      "resolved": "https://registry.npmjs.org/es6-shim/-/es6-shim-0.35.3.tgz",
+      "integrity": "sha1-m/tzY/7//4emzbbNk+QF7DxLbyY="
+    },
     "es6-symbol": {
       "version": "3.1.1",
       "resolved": "https://registry.npmjs.org/es6-symbol/-/es6-symbol-3.1.1.tgz",

test/endtoend/create-react-app/package.json

@@ -4,6 +4,7 @@
   "private": true,
   "homepage": "/create-react-app/",
   "dependencies": {
+    "es6-shim": "^0.35.3",
     "react": "^16.4.1",
     "react-dom": "^16.4.1",
     "react-scripts": "1.1.4"

test/endtoend/create-react-app/src/index.js

@@ -1,3 +1,4 @@
+import 'es6-shim' // Polyfill Map and Set for React
 import React from 'react'
 import ReactDOM from 'react-dom'
 import App from './App'