Furthermore avoid lock-step between pointer updating phases as they
should execute in parallel without synchronization restrictions.

Bug: chromium:726040
Change-Id: I26ce0d1f2a4637ff5610cae556113e3d736788e2
Reviewed-on: https://chromium-review.googlesource.com/518103
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45574}