Documenting UserFlow.endFailure
Documenting UserFlow.endFailure

Summary:
We had some confusion lately, where errorName was used to dump "error message". This caused problems in Scuba.
This doc should add some clarity on what is expected from endFailure users.

Changelog:
[Internal][Added] - Documentation for method in UserFlow.js class

Reviewed By: mityal

Differential Revision: D30192127

fbshipit-source-id: d057668aab714a9342131c83daf41cbe9372cb39

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