Repro steps:
1. Open attached project
2. Enter Play Mode and observe the values in Game View
3. Exit Play Mode
4. File -> Build and Run
5. Play the game and observe the values again

Expected: value_ is non-negative
Actual: value_ is negative

Reproducible with: 2018.1.9f1, 2018.2.0f2

Notes:
- Only in .NET 4.x
- The Class must have a reference to another Class and an Enum variable
- The Enum variable must be declared next to the Class reference
- This doesn't happen when there's a typeof(Enum) statement

Fixed in: 2018.3.0a10
Backported to: 2018.2.8f1