Error in the new version of flow 0.55

Library in version : immutable@4.0.0-rc.2

To get this error just run flow:

```
Error: node_modules/immutable/dist/immutable.js.flow:519
519:   static of<T>(...values: T[]): SetSeq<T>;
                                     ^^^^^^^^^ SetSeq. This type is incompatible with
383:   static of<T>(...values: T[]): IndexedSeq<T>;
                                     ^^^^^^^^^^^^^ IndexedSeq
```