update JavaScript bindings

Summary:
- adds flow types
- transpiles bundle using babel
- cleans and formats code

Reviewed By: emilsjolander

Differential Revision: D6748362

fbshipit-source-id: fcb5fdde73df6e0062eff1e5038bb5fe0532f997

javascript/sources/entry-node.js

@@ -5,9 +5,25 @@
  * 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
+ * @format
  */
 
-var nbind = require('nbind');
-var ret = nbind.init(__dirname + '/../');
-
-module.exports = require('./entry-common')(ret.bind, ret.lib);
+import Yoga from './entry-common';
+const nbind = require('nbind');
+const {bind, lib} = nbind.init(__dirname + '/../');
+module.exports = Yoga(bind, lib);
+export type {
+  Yoga$JustifyContent,
+  Yoga$Align,
+  Yoga$FlexDirection,
+  Yoga$Direction,
+  Yoga$FlexWrap,
+  Yoga$Edge,
+  Yoga$Display,
+  Yoga$Unit,
+  Yoga$Overflow,
+  Yoga$PositionType,
+  Yoga$ExperimentalFeature,
+} from './YGEnums.js';