Make RCTEventEmitter synthesize RCTViewRegistry
Make RCTEventEmitter synthesize RCTViewRegistry

Summary:
This will help us migrate our iOS EventEmitters off the bridge.

Changelog: [Internal]

Reviewed By: shergin

Differential Revision: D25656902

fbshipit-source-id: 2ca434e073383a1bf5b1d7366f1e1858c0c49aa6

janicduplessis/react-native,facebook/react-native,arthuralee/react-native,janicduplessis/react-native,myntra/react-native,javache/react-native,arthuralee/react-native,pandiaraj44/react-native,janicduplessis/react-native,janicduplessis/react-native,janicduplessis/react-native,javache/react-native,janicduplessis/react-native,facebook/react-native,facebook/react-native,javache/react-native,pandiaraj44/react-native,facebook/react-native,pandiaraj44/react-native,myntra/react-native,arthuralee/react-native,javache/react-native,facebook/react-native,facebook/react-native,janicduplessis/react-native,pandiaraj44/react-native,javache/react-native,myntra/react-native,janicduplessis/react-native,javache/react-native,myntra/react-native,myntra/react-native,facebook/react-native,facebook/react-native,javache/react-native,myntra/react-native,pandiaraj44/react-native,arthuralee/react-native,myntra/react-native,pandiaraj44/react-native,pandiaraj44/react-native,myntra/react-native,javache/react-native,pandiaraj44/react-native,javache/react-native,arthuralee/react-native,facebook/react-native,myntra/react-native