The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0cb936b2af146db2e9d1e43cf7fc1aae5a18d798

commit 0cb936b2af146db2e9d1e43cf7fc1aae5a18d798
Author: Christopher Grant <cjgrant@chromium.org>
Date: Wed Nov 15 16:12:22 2017

VR: Fix initial visibility of WebVR splash screen elements.

In tests and testapp situations, the default UI should be a non-WebVR, browser
environment, based on the default initial state.  However, some elements
were visible by default, causing the first frame to show them in lieu of
expected elements.

BUG= 783975 

Change-Id: Id2b3008a9886d96df953fbe19da6d9a877601e01
Reviewed-on: https://chromium-review.googlesource.com/769831
Reviewed-by: Ian Vollick <vollick@chromium.org>
Reviewed-by: Yash Malik <ymalik@chromium.org>
Commit-Queue: Christopher Grant <cjgrant@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516711}
[modify] https://crrev.com/0cb936b2af146db2e9d1e43cf7fc1aae5a18d798/chrome/browser/vr/ui.cc
[modify] https://crrev.com/0cb936b2af146db2e9d1e43cf7fc1aae5a18d798/chrome/browser/vr/ui_scene_manager.cc

Testers:  No need to explicitly verify anything here, IMO, this only affects our tests/testapp.