The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4b2bd9cbc293d585bcf3d53ba2339e535e006c06

commit 4b2bd9cbc293d585bcf3d53ba2339e535e006c06
Author: Ian Vollick <vollick@chromium.org>
Date: Mon Sep 18 20:43:22 2017

[vr] Create a background for the splash screen text

Previously, we'd relied on the skybox to provide this background, but
this is incorrect.

In order to get the splash screen text to render in front of the
background, I've generalized the notion of "draw phase" and have used
it to gather collections of renderable elements in vr_shell_gl
to pass to the UiRenderer.

I've also added the notion of a RenderableElement to help elide and
ignore elements that could never draw, regardless of their visibility.

Bug:  763552 
Change-Id: If94d3945e8f1c8ca2ff7b9b449139fc845271699
Reviewed-on: https://chromium-review.googlesource.com/658068
Reviewed-by: Christopher Grant <cjgrant@chromium.org>
Reviewed-by: Biao She <bshe@chromium.org>
Reviewed-by: Yash Malik <ymalik@chromium.org>
Commit-Queue: Ian Vollick <vollick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#502665}
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/android/vr_shell/vr_shell_gl.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/BUILD.gn
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/draw_phase.h
[add] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/full_screen_rect.cc
[add] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/full_screen_rect.h
[delete] https://crrev.com/5191288fe9999c8bbafc0a70dbcf44a145a023ca/chrome/browser/vr/elements/screen_dimmer.cc
[delete] https://crrev.com/5191288fe9999c8bbafc0a70dbcf44a145a023ca/chrome/browser/vr/elements/screen_dimmer.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/textured_element.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/ui_element.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/ui_element.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/ui_element_name.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/viewport_aware_root.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/elements/viewport_aware_root_unittest.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/test/ui_scene_manager_test.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/test/ui_scene_manager_test.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_renderer.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_renderer.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_scene.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_scene.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_scene_manager.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_scene_manager.h
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_scene_manager_unittest.cc
[modify] https://crrev.com/4b2bd9cbc293d585bcf3d53ba2339e535e006c06/chrome/browser/vr/ui_scene_unittest.cc