I loaded https://github.com/gearvrf/GearVRf-Demos/tree/master/gvr-camera2renderscript/ to an S9+ running Android 9.0 and the screen is black.
Phone OS Status
S9+ 8.0 PASS
S9+ 9.0 FAIL
I am unable to recreate this on an S8 or S8+ and only seems to affect S9+ running 9.0.