The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265

commit d6eb0c60433edd4f0bc0b6435a57a9143a6ff265
Author: Iker Jamardo <ijamardo@chromium.org>
Date: Thu Jun 07 18:10:20 2018

Request camera permission when AR features are requested.

Adds a new XRSessionRequest structure to be passed when the
RequestSession call is made to be able to pass information like
user gesture. The RequestSession now requests camera permission
in ARCoreDevice. The code to ask for camera permission has been
copied and adapted from
src/chrome/browser/media/webrtc/media_stream_devices_controller.cc
and a re-check for the Android OS level camera permission is still
needed.

Bug:  835037 ,  845160 , 775372
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_vr
Change-Id: Iecabc3927beb6106a1ada5289f3af3ecffd48ed8
Reviewed-on: https://chromium-review.googlesource.com/1055677
Commit-Queue: Iker Jamardo <ijamardo@chromium.org>
Reviewed-by: David Dorwin <ddorwin@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Bill Orr <billorr@chromium.org>
Reviewed-by: Raymes Khoury <raymes@chromium.org>
Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565347}
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_device.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_device.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_gl.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_gl.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_gl_thread.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_gl_thread.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/android/vr/arcore_device/arcore_impl.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/geolocation/geolocation_permission_context_android.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/media/webrtc/media_stream_devices_controller.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/permissions/permission_update_infobar_delegate_android.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/permissions/permission_update_infobar_delegate_android.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/vr/service/vr_display_host.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/chrome/browser/vr/service/vr_display_host.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/public/mojom/vr_service.mojom
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/test/mock_vr_display_impl.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/test/mock_vr_display_impl.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_device.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_device_base.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_device_base.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_device_base_unittest.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_display_impl.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_display_impl.h
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/device/vr/vr_display_impl_unittest.cc
[modify] https://crrev.com/d6eb0c60433edd4f0bc0b6435a57a9143a6ff265/third_party/blink/renderer/modules/xr/xr_device.cc

I'm going to call this fixed. There is more work we want to do to simplify initialization in issue 849568.