The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/18732d771d2b10a39707d4bdda57e3a367dac55d

commit 18732d771d2b10a39707d4bdda57e3a367dac55d
Author: tiborg <tiborg@chromium.org>
Date: Thu Apr 06 16:51:58 2017

Fixes WebVR presentation from within VRShell.

- VrShellDelegate delays the call of a successfull request present callback until the GL thread is ready.
- By doing so, VrShellDelegate is able to pass the VRSubmitFrameClient to the GL thread no matter if the Gl thread was ready at the time of the request.
- Previously, the VRSubmitFrameClient was only passed correctly if the GL thread was not ready at the time of the request. Thus, WebVR presentation crashed from within VRShell.

BUG= 703324 

Review-Url: https://codereview.chromium.org/2774933003
Cr-Commit-Position: refs/heads/master@{#462511}

[modify] https://crrev.com/18732d771d2b10a39707d4bdda57e3a367dac55d/chrome/browser/android/vr_shell/vr_shell.cc
[modify] https://crrev.com/18732d771d2b10a39707d4bdda57e3a367dac55d/chrome/browser/android/vr_shell/vr_shell.h
[modify] https://crrev.com/18732d771d2b10a39707d4bdda57e3a367dac55d/chrome/browser/android/vr_shell/vr_shell_delegate.cc
[modify] https://crrev.com/18732d771d2b10a39707d4bdda57e3a367dac55d/chrome/browser/android/vr_shell/vr_shell_delegate.h
[modify] https://crrev.com/18732d771d2b10a39707d4bdda57e3a367dac55d/device/vr/android/gvr/gvr_delegate.h