Upgrade Babel to version 7.0.0 (#5925)

babel.config.js

@@ -0,0 +1,65 @@
+module.exports = (api) => {
+  const env = api.env();
+
+  const envOptions = {
+    debug: false,
+    loose: true,
+    modules: false,
+  };
+
+  const config = {
+    presets: [
+      '@babel/react',
+      ['@babel/env', envOptions],
+    ],
+    plugins: [
+      '@babel/syntax-dynamic-import',
+      ['@babel/proposal-object-rest-spread', { useBuiltIns: true }],
+      ['@babel/proposal-decorators', { legacy: true }],
+      '@babel/proposal-class-properties',
+      ['react-intl', { messagesDir: './build/messages' }],
+      'preval',
+    ],
+  };
+
+  switch (env) {
+  case 'production':
+    envOptions.debug = false;
+    config.plugins.push(...[
+      'lodash',
+      [
+        'transform-react-remove-prop-types',
+        {
+          mode: 'remove',
+          removeImport: true,
+          additionalLibraries: [
+            'react-immutable-proptypes',
+          ],
+        },
+      ],
+      '@babel/transform-react-inline-elements',
+      [
+        '@babel/transform-runtime',
+        {
+          helpers: true,
+          regenerator: false,
+          useESModules: true,
+        },
+      ],
+    ]);
+    break;
+  case 'development':
+    envOptions.debug = true;
+    config.plugins.push(...[
+      '@babel/transform-react-jsx-source',
+      '@babel/transform-react-jsx-self',
+    ]);
+    break;
+  case 'test':
+    envOptions.modules = 'commonjs';
+    break;
+  }
+
+  return config;
+};
+