The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d586e7bf97f545f9d78bad427dcf821903de2b41

commit d586e7bf97f545f9d78bad427dcf821903de2b41
Author: Mohsen Izadi <mohsen@chromium.org>
Date: Wed Dec 12 21:12:06 2018

Enable out-of-process viz service only when necessary

Viz process that can be run using service manager is only used when mash
is run in multi-process mode with out-of-process viz (i.e. when both
Mash and MashOopViz features or on). Currently, service manager uses
aura::Env mode (MUS vs LOCAL) to allow this which is wrong. Also, a
recent change (r611340) causes service manager to run before aura::Env
is created which breaks things further. This CL checks Mash and
MashOopViz features to allow out-of-process viz.

BUG=912218

Change-Id: Ib828acefd07abcb9ab134c9ed866fc3d4792de40
Reviewed-on: https://chromium-review.googlesource.com/c/1373883
Reviewed-by: Ken Rockot <rockot@google.com>
Commit-Queue: Mohsen Izadi <mohsen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#616041}
[modify] https://crrev.com/d586e7bf97f545f9d78bad427dcf821903de2b41/content/browser/service_manager/service_manager_context.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b8bfbe4f05728417fd40100cfe05b005fa4eedd3

commit b8bfbe4f05728417fd40100cfe05b005fa4eedd3
Author: Mohsen Izadi <mohsen@chromium.org>
Date: Fri Dec 21 07:18:35 2018

Allow mash run viz process if MashOopViz is enabled

If MashOopViz features is enabled, multi-process mash should try to bind
VizMain pointer to the implementation in viz process.

BUG=912218

Change-Id: Id32b4192994299885e62428b868222cea33b621f
Reviewed-on: https://chromium-review.googlesource.com/c/1381635
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Mohsen Izadi <mohsen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#618476}
[modify] https://crrev.com/b8bfbe4f05728417fd40100cfe05b005fa4eedd3/ash/manifest.json
[modify] https://crrev.com/b8bfbe4f05728417fd40100cfe05b005fa4eedd3/services/viz/manifest.json
[modify] https://crrev.com/b8bfbe4f05728417fd40100cfe05b005fa4eedd3/services/ws/gpu_host/gpu_host.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f1958f2fd7af2f1cb015b8e5b6685e9e3c06fb82

commit f1958f2fd7af2f1cb015b8e5b6685e9e3c06fb82
Author: Mohsen Izadi <mohsen@chromium.org>
Date: Fri Jan 18 20:29:31 2019

Set viz service message loop type according to ozone platform

For some ozone platforms (specifically X11), main message loop of the
viz process should be of type UI. So, when service manager starts viz
service, it should set its message loop type according to the ozone
platform.

BUG=912218

Change-Id: I7859e08478b9c146733620c858c8a75017c8743e
Reviewed-on: https://chromium-review.googlesource.com/c/1420199
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Mohsen Izadi <mohsen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#624262}
[modify] https://crrev.com/f1958f2fd7af2f1cb015b8e5b6685e9e3c06fb82/chrome/browser/chrome_content_browser_client.cc

r625015 landed as part of this issue (not sure why bugdroid didn't add the comment):

  Move ozone drm interface registration to VizMainImpl

  This CL moves registration of ozone drm mojo interfaces to VizMainImpl,
  so everywhere VizMainImpl is created, those interfaces are registered
  automatically. Clients would need to ask VizMainImpl to bind requests
  for those interfaces.

  This is a cleanup for enabling out-of-process viz service in
  multi-process mash, however it also fixes an issue in multi-process mash
  with in-process viz where drm interfaces are registered on the wrong
  thread (crbug/909736).

  BUG=912218,909736

  Change-Id: I4028e023e48c57e5a99e11321ed701435eaf96b3
  Reviewed-on: https://chromium-review.googlesource.com/c/1426161
  Commit-Queue: Mohsen Izadi <mohsen@chromium.org>
  Reviewed-by: Scott Violet <sky@chromium.org>
  Cr-Commit-Position: refs/heads/master@{#625015}