Steps to reproduce:
1. Open attached project "937501.zip"
2. Build 'main' scene for UWP
3. Open VS solution
4. Build & run on local machine
5. After launch observe VS output
you can see that the string value is printed out in 'OnAfterDeserialize()'
right after 'OnStateEnter()' is called, however, the string value(which was printed out before) is null
in this case, integer member value remains the same, while string member value gets nulled

Expected behavior: 'OnAfterDeserialize()' doesn't erase string member value on finish

Notes:
Not reproducible in Editor
Not reproducible with IL2CPP scripting backend

Reproducible with: 5.6.0b1, 5.6.3f1, 2017.1.0p3, 2017.2.0b5, 2017.3.0a2

Fixed in: 2017.3.0b8, 2018.1.0a3