GitLab

Use the IdentityManager APIs and update callers accordingly,
including calls from the associated test suite.

Bug: 889879
Change-Id: I69c1c29d033602dd0c37618fefd71c5229ceacbe
Reviewed-on: https://chromium-review.googlesource.com/1251609Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Mario Sanchez Prada <mario@igalia.com>
Cr-Commit-Position: refs/heads/master@{#595407}