Repro steps:
1. Open user attached project
2. Open scene "Test"
3. Enter Play Mode
4. Press the Button in the Game View and observe the Console

A message is logged in the Console "Received Argument ....."

5. Exit Play Mode
6. Create an Assembly Definition file anywhere in the project
7. Wait for the Editor to Hot Reload
8. Repeat steps 3 and 4

Expected: The same message is logged in the Console
Actual: No messages in the Console and on the Button component of the Button GameObject in the OnClick section the method is identified as <Missing>

Reproducible with: 2017.4.14f1, 2018.2.14f1, 2018.3.0b7, 2019.1.0a6

Notes:
- Re-selecting that method in the OnClick section of the Button component fixes the issue