TextInput onChangeText and onSelectionChange out of order

[rozele]

Steps To Reproduce

https://user-images.githubusercontent.com/1106239/117464936-25535f80-af1f-11eb-8069-afaa710e596f.mov
Provide a detailed list of steps that reproduce the issue.

1. Open RNTester > TextInput component example > Text selection & cursor placement
2. Set breakpoints in onChangeText and onSelectionChange
3. Observe the order of events

Expected Results

On iOS, Android, and macOS, the order of events is onChangeText -> onSelectionChange. On Windows, the order of events is reversed.

Snack, code example, screenshot, or link to a repository:

Windows:

2021-05-07.10-23-31.mp4

Android:

Screen.Recording.2021-05-07.at.10.25.38.AM.mov

iOS:

Screen.Recording.2021-05-07.at.10.28.43.AM.mov