Reproduction steps:
(Check the attached video
1. Open the project (link is in the edit)
2. Open the scene
3. Hit play
4. Walk towards the chair.
5. You should see that the light behind the chair is turning on and off, depending how you position the camera

Expected: lights look the same from any angle
Actual: lights are invisible.

Tested with 5.5.0b2,5.5.0b5
Couldn't check for regression because if the project is opened in an earlier version of Unity, it just crashes.