Modifying a Static Mesh's "Y" Collision Rotation also modifies "X" and "Z" Rotation

If the user modifies the "Y" Rotation value of a Static Mesh's Collision, the "X" and "Z" values are changed.

The values will move +/- 1 point from their value prior to modifying the Y value.
This effect is observed if the user Scrubs the value or enters it manually.

Because this functionality did not exist in 4.14.0 / 4.14.1, this issue is not marked as a regression.

1. Open UE4Editor
2. Open a Static Mesh in the Static Mesh Editor (Default Cube was used in the example)
3. Add a Box Simplified Collision
4. Within the Details panel, expand Collision > Primitives > Boxes
5. Scrub the "Y" Rotation value

Result:
Modifying the "Y" Collision Rotation value also modifies "X" and "Z" Rotation

Frequency:
5/5