GitLab

Define a provider that needs to be implemented by embedders to provide
embedder specific values.

Change-Id: I33f929b7a26b997a293dd9e080126214c58fdefe
Bug: 1062743
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2119765Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Commit-Queue: John Wu <jzw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#754556}