RNFS.stat reports file not exists, but RNFS.exists reports file exists.

The code that call RNFS.stat (version 2.9.11) works.

But after I upgrade RNFS to the latest version, and RNFS.stat always run into exception, says file does not exists.

My sample code:

```
let path='file:///data/user/0/com.fzbdemo8/cache/1531620707190.JPEG'
RNFS.stat(path).then(
(stat)=>{}
).catch((err) => {
console.log(err.message, err.code); //run into exception
});
```

The file do exists.