To reproduce:

1. Download and open attached "GearVRLoadDevice.zip" project.
2. Add oculus signature file for target device.
3. Build and deploy to device.
4. The scene will attempt to toggle VR on/off every 3 seconds (note the countdown).

Expected result: After 3 second countdown VR mode toggles off and application quits stereo rendering(GearVR) mode.
Actual result: After 3 seconds rendering mode is not changed. It continues to stay in GearVR mode.

Reproduced with: 2018.1.0a6, 2017.3.0b11, 2017.2.0p4, 2017.1.2p3, 5.6.4p3, 5.6.0b5.
Not reproduced with: 5.6.0b4, 5.5.5p2.
Regression introduced in: 5.6.0b5.

Devices under test:

Samsung SM G928F*, OS:7.0, CPU:arm64-v8a, GPU:Mali-T760,
Build:samsung/zenltexx/zenlte:7.0/NRD90M/G928FXXU3CQG2:user/release-keys

Samsung SM G950U*, OS:7.0, CPU:arm64-v8a, GPU:Adreno (TM) 540,
Build:samsung/dreamqltesq/dreamqltesq:7.0/NRD90M/G950USQU1AQC8:user/release-keys

Verizon SM G930V*, OS:6.0.1, CPU:arm64-v8a, GPU:Adreno (TM) 530,
Build:Verizon/heroqltevzw/heroqltevzw:6.0.1/MMB29M/G930VVRU2APG3:user/release-keys

Notes: Did not reproduce with Cardboard or Daydream VR SDK's. In Unity 5.6.0b4 toggling from VR to non-VR mode works, however, after toggling, non-VR mode renders only blackscreen.