To reproduce (with attached project):
1. Open project
2. Play scene

Repro steps with new project:
1. Create a standard point light, add light to new layer (Lights)
2. Create a prefab of the light
3. Create a particle system with the light module enabled.
4. Add the light prefab to the particle system light module.
5. Create a separate light camera, culling everything except the light layer.
6. Uncheck the light layer from the main camera's culling mask.

Expected vs Actual: particle's lights are not visible in game view

Reproduced on: 5.5.4p1, 5.6.3p4, 2017.1.1p3, 2017.2.0f1, 2017.3.0b2