Summary:
Related to #22100
Turn Flow strict mode on for ScrollViewMock.
This file used to declare jest var as `any` but jest module is already typed in root flow folder.
Note: I had to use a quick fix for polyfillPromise. See here #22101
- All flow tests succeed.
[GENERAL] [ENHANCEMENT] [ScrollViewMock.js] - Flow strict mode
Pull Request resolved: https://github.com/facebook/react-native/pull/22103
Differential Revision: D12918380
Pulled By: TheSavior
fbshipit-source-id: cd3aba47b1a43e76a7da09e15cc2d9cfcdf7f56d
499c195eba