Phones with no magnetometer -> GetInputMotionState returns all 0s

Bug submission from a user overseas:

" On some devices (Moto G5 Plus, Moto G5 S Plus) the values are always 0 like : Tilt : 0.00.00.0 RotationRate : 0.00.00.0 Gravity : 0.00.00.0 Accleration : 0.00.00.0. In the android logs, the following error is seen : SensorManager : sensor or listener is null."

" I took a look at the code that UE generates for android (GameActivity.java)
and it looks like if the magnetometer is null, then no values are
calculated"

" I have found that the engine code only proceeds if magnetometer and accelerometer are both not null. The values we want are not dependent on the magnetometer but we are unable to get the values because of the implementation."

~

Chris B: "We use the magnetometer to get the proper orientation frame. Without it the heading will float which means all the axes aren't guaranteed to mean anything"

1. Acquire Mobile phone without magnetometer ( [Link Removed] )
2. Attempt to deploy to mobile using GetInputMotionState
3. Observe that all values from InputMotionState return 0

Input Motion Events not working in UE 4.19

Input Motion State is always 0