Break out defaults, add flow for Config

Summary: In order to make `Config` and defaults available to our new code, I’ve added flow types and put default values into one shared modile

Reviewed By: cpojer

Differential Revision: D4044600

fbshipit-source-id: 875ed3ade69c5b22bb3c1b177e7bad732834d476

packager/defaults.js

@@ -0,0 +1,49 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @flow
+ */
+'use strict';
+
+exports.assetExts =  [
+  'bmp', 'gif', 'jpg', 'jpeg', 'png', 'psd', 'svg', 'webp', // Image formats
+  'm4v', 'mov', 'mp4', 'mpeg', 'mpg', 'webm', // Video formats
+  'aac', 'aiff', 'caf', 'm4a', 'mp3', 'wav', // Audio formats
+  'html', 'pdf', // Document formats
+];
+
+exports.moduleSystem = require.resolve('./react-packager/src/Resolver/polyfills/require.js');
+
+exports.platforms = ['ios', 'android', 'windows', 'web'];
+
+exports.polyfills = [
+  require.resolve('./react-packager/src/Resolver/polyfills/polyfills.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/console.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/error-guard.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/Number.es6.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/String.prototype.es6.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/Array.prototype.es6.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/Array.es6.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/Object.es7.js'),
+  require.resolve('./react-packager/src/Resolver/polyfills/babelHelpers.js'),
+];
+
+exports.providesModuleNodeModules = [
+  'react-native',
+  'react-native-windows',
+  // Parse requires AsyncStorage. They will
+  // change that to require('react-native') which
+  // should work after this release and we can
+  // remove it from here.
+  'parse',
+];
+
+exports.runBeforeMainModule = [
+  // Ensures essential globals are available and are patched correctly.
+  'InitializeCore',
+];