Steps to reproduce:

1. Open attached project
2. Open "test" scene
3. Press play
4. Hold space
("Cube" is rotating around towards the red line)
5. Notice how "Cube" rotation breaks when reaching -90 degrees(gif attached)

Expected behavior: according to unity docs "The current vector will be rotated round toward the target direction by an angle of maxRadiansDelta, although it will land exactly on the target rather than overshoot." Since the direction(the "Cube" object is rotating towards) is a child object of "Cube" it would make sense that "Cube" will never land on the target and should be rotating infinitely.

Reproduced with: 5.2.4f1, 5.3.6f1, 5.4.0f2