Remove RocksDB
Remove RocksDB

Summary:
@public
RocksDB was originally available when RN open sourced but is no longer used, so removing it from AsyncStorage.js.
Changelog: [General] Removed RocksDB from AsyncStorage.js

Reviewed By: fkgozali

Differential Revision: D15218709

fbshipit-source-id: 82993f86bbb3f32e61d1e9895aafd67701351860

facebook/react-native,hoangpham95/react-native,hoangpham95/react-native,hammerandchisel/react-native,janicduplessis/react-native,javache/react-native,janicduplessis/react-native,exponent/react-native,hammerandchisel/react-native,myntra/react-native,myntra/react-native,myntra/react-native,hammerandchisel/react-native,exponent/react-native,myntra/react-native,javache/react-native,myntra/react-native,janicduplessis/react-native,hoangpham95/react-native,hoangpham95/react-native,facebook/react-native,exponent/react-native,pandiaraj44/react-native,exponentjs/react-native,janicduplessis/react-native,hammerandchisel/react-native,janicduplessis/react-native,javache/react-native,arthuralee/react-native,arthuralee/react-native,facebook/react-native,exponentjs/react-native,pandiaraj44/react-native,pandiaraj44/react-native,exponentjs/react-native,pandiaraj44/react-native,arthuralee/react-native,exponentjs/react-native,pandiaraj44/react-native,myntra/react-native,exponentjs/react-native,exponentjs/react-native,exponentjs/react-native,javache/react-native,javache/react-native,facebook/react-native,facebook/react-native,hoangpham95/react-native,hoangpham95/react-native,facebook/react-native,pandiaraj44/react-native,javache/react-native,myntra/react-native,javache/react-native,exponent/react-native,pandiaraj44/react-native,myntra/react-native,hammerandchisel/react-native,myntra/react-native,exponent/react-native,hoangpham95/react-native,janicduplessis/react-native,hoangpham95/react-native,arthuralee/react-native,hammerandchisel/react-native,exponent/react-native,hammerandchisel/react-native,arthuralee/react-native,javache/react-native,janicduplessis/react-native,exponent/react-native,javache/react-native,exponent/react-native,facebook/react-native,pandiaraj44/react-native,facebook/react-native,facebook/react-native,exponentjs/react-native,janicduplessis/react-native,hammerandchisel/react-native