The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/43fd1f406f081f94a50f124cd8bbee283ad10fc0

commit 43fd1f406f081f94a50f124cd8bbee283ad10fc0
Author: Eric Karl <ericrk@chromium.org>
Date: Thu Aug 02 01:00:00 2018

Android OOP-D: Pass alpha preferences to VizProcessContextProvider

Currently VizProcessContextProvider assumes no alpha. Android needs
alpha in cases where it is rendering on top of a video overlay. Plumb
the alpha request through via RendererSettings.

Bug:  869131 
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I6c51a07b141e61d95b2e25183156ebf15daeca38
Reviewed-on: https://chromium-review.googlesource.com/1155715
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: kylechar <kylechar@chromium.org>
Commit-Queue: Eric Karl <ericrk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580015}
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/cc/test/pixel_test.cc
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/components/viz/common/display/renderer_settings.h
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/components/viz/service/display_embedder/gpu_display_provider.cc
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/components/viz/service/display_embedder/viz_process_context_provider.cc
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/components/viz/service/display_embedder/viz_process_context_provider.h
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/content/browser/renderer_host/compositor_impl_android.cc
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/services/viz/privileged/interfaces/compositing/renderer_settings.mojom
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/services/viz/privileged/interfaces/compositing/renderer_settings_struct_traits.cc
[modify] https://crrev.com/43fd1f406f081f94a50f124cd8bbee283ad10fc0/services/viz/privileged/interfaces/compositing/renderer_settings_struct_traits.h

Remaining part of this is being handled by cblume@. over to him.

Landed over here:
https://chromium-review.googlesource.com/c/chromium/src/+/1155841
(I forgot to add this bug though)