Chrome Version: 71.0.3569.0
OS: Win 10
VR Headset: Windows Mixed Reality

Note: This works on the same machine and Chrome instance with the HTC Vive headset.

Repro steps:
(1) Set up machine and Chrome to use Windows Mixed Reality device. (Chrome flags, Steam, etc.)
(2) Go to https://immersive-web.github.io/webxr-samples/tests/permission-request.html and click "Enter VR".
(3) In headset, click the camera icon.
(4) Remove headset and click "Allow" in the Chrome premission prompt to use your camera.
(5) Place the headset back on.

Expected: The camera icon should change to a green check mark.

Actual: The camera icon has changed to a red X.