The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/582b854a42002ff2b085b5ea794da8e0e5c2cd56

commit 582b854a42002ff2b085b5ea794da8e0e5c2cd56
Author: Bill Orr <billorr@chromium.org>
Date: Fri Jul 06 22:29:57 2018

Clean up OvrSession lifetime for Oculus device.

For querying basic hardware information, or supporting magic window,
we shouldn't initialize the Oculus runtime for presenting.  We were
using the Oculus APIs on multiple threads in a way that isn't thread
safe.  The multithreaded usage of ovrSessions also prevented correctly
handling errors like device-lost.

This change makes it so we have different OvrSessions for presenting or
non-presenting, and we only have one of these sessions initialized at a time.
The gamepad data now comes from the OculusRenderLoop, so we aren't using the
Oculus API on 3 separate threads.

We aren't passing the sessions around between threads, so this also makes it more
clear that we are using the API in a threadsafe way.

BUG= 852456 ,  838433 ,  793364 

Change-Id: I4f21ce4d59c081f0e1730b52cc12d1819369a436
Reviewed-on: https://chromium-review.googlesource.com/1116241
Commit-Queue: Bill Orr <billorr@chromium.org>
Reviewed-by: Klaus Weidner <klausw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#573093}
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_device.cc
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_device.h
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_device_provider.cc
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_device_provider.h
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_gamepad_data_fetcher.cc
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_gamepad_data_fetcher.h
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_render_loop.cc
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/oculus/oculus_render_loop.h
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/windows/d3d11_texture_helper.cc
[modify] https://crrev.com/582b854a42002ff2b085b5ea794da8e0e5c2cd56/device/vr/windows/d3d11_texture_helper.h