Summary:
Removes the deprecated APIs that were replaced by `RefreshControl`. Those API have been deprecated for a while already so I think it's fine to remove them at this point. Also ported the `SwipeRefreshLayoutTestModule` test to use `RefreshControl` instead of `PullToRefreshViewAndroid`.
**Test plan (required)**
Made sure no references are left in the codebase to `PullToRefreshViewAndroid`, `onRefreshStart` and `endRefreshing`.
Tested that `ScrollView` examples in UIExplorer still work properly.
Check that the `SwipeRefreshLayoutTestModule` passes on CI.
Closes https://github.com/facebook/react-native/pull/7447
Reviewed By: mkonicek
Differential Revision: D3292391
Pulled By: bestander
fbshipit-source-id: 27eb2443861e04a9f7319586ce2ada381b714d47
a71a9efe96