Reproduction steps:
1. Open the attached project AI Learning.zip;
2. Open the BakeTimeTest scene;
3. Observe the inside of the Room;
4. Observe the floor of the Room;
5. Notice that the light leaks through the wall, even if it should be blocked off.

Expected results: The walls have to block the light and the room has to be unlit.
Actual results: The lights are leaking through the walls.

Reproduced with: 5.5.0b1, 5.5.0b4, 5.5.0b5 and 5.5.0b6 versions of Unity. Not reproduced with older versions because of the errors in the Console.

Workaround:
1. The directional and point lights' Bias and Normal Bias could be changed to 0;
2. The walls can be duplicated and then set on the different layer, so the light will not affect them.