BREAKING: Add regenerator-runtime on demand, based on the files

Summary:
Adding a Babel plugin that will analyze the file looking for any potential candidate to use `regenerator-runtime`, and if so, will inject dynamically the module. The module is injected per file, so we avoid polluting the global environment. The plugin is also able to inject the `require` call beforehand, so that the inliner can pick them and inline them.

The Babel plugin is part of `react-native-babel-preset`, so as long as you are using this preset you are safe. If not, you should include the specific transformer into your list of plugins, as `react-native-babel-preset/transforms/transform-regenerator-runtime-insertion.js`.

Reviewed By: davidaurelio

Differential Revision: D5388655

fbshipit-source-id: dc403f3d5e2d807529eb8569a85c45fec36a6a3e

Libraries/Core/InitializeCore.js

@@ -138,15 +138,6 @@ defineProperty(global, 'Set', () => require('Set'), true);
 // ERROR: Event loop not supported.
 defineProperty(global, 'Promise', () => require('Promise'));
 
-// Set up regenerator.
-defineProperty(global, 'regeneratorRuntime', () => {
-  // The require just sets up the global, so make sure when we first
-  // invoke it the global does not exist
-  delete global.regeneratorRuntime;
-  require('regenerator-runtime/runtime');
-  return global.regeneratorRuntime;
-});
-
 // Set up timers
 const defineLazyTimer = name => {
   defineProperty(global, name, () => require('JSTimers')[name]);

RNTester/js/ListExampleShared.js

@@ -163,11 +163,11 @@ const THUMB_URLS = [
   require('./Thumbnails/victory.png'),
 ];
 
-const LOREM_IPSUM = 'Lorem ipsum dolor sit amet, ius ad pertinax oportere accommodare, an vix \
+const LOREM_IPSUM = 'Lorem ipsum dolor sit amet, ius ad pertinax oportere accommodare, an vix ' +
-civibus corrumpit referrentur. Te nam case ludus inciderint, te mea facilisi adipiscing. Sea id \
+  'civibus corrumpit referrentur. Te nam case ludus inciderint, te mea facilisi adipiscing. Sea id ' +
-integre luptatum. In tota sale consequuntur nec. Erat ocurreret mei ei. Eu paulo sapientem \
+  'integre luptatum. In tota sale consequuntur nec. Erat ocurreret mei ei. Eu paulo sapientem ' +
-vulputate est, vel an accusam intellegam interesset. Nam eu stet pericula reprimique, ea vim illud \
+  'vulputate est, vel an accusam intellegam interesset. Nam eu stet pericula reprimique, ea vim illud ' +
-modus, putant invidunt reprehendunt ne qui.';
+  'modus, putant invidunt reprehendunt ne qui.';
 
 /* eslint no-bitwise: 0 */
 function hashCode(str: string): number {

babel-preset/package.json

@@ -1,6 +1,6 @@
 {
   "name": "babel-preset-react-native",
-  "version": "2.0.0",
+  "version": "2.1.0",
   "description": "Babel preset for React Native applications",
   "main": "index.js",
   "repository": "https://github.com/facebook/react-native/tree/master/babel-preset",

package.json

@@ -150,7 +150,7 @@
     "babel-polyfill": "^6.20.0",
     "babel-preset-es2015-node": "^6.1.1",
     "babel-preset-fbjs": "^2.1.4",
-    "babel-preset-react-native": "^2.0.0",
+    "babel-preset-react-native": "^2.1.0",
     "babel-register": "^6.24.1",
     "babel-runtime": "^6.23.0",
     "babel-traverse": "^6.24.1",