GitLab

Use IdentityTestEnvironmentChromeBrowserStateAdaptor instead of manually
creating the browser's state by providing specific factories, and then
use the APIs from IdentityTestEnvironment, instead of SigninManagerBase.

Also remove an unnecessary DCHECK in clear_browsing_data_manager_unittest.mm,
as pointed out post-review when fixing crbug.com/890826 (CL 1318974).

Bug: 903703
Change-Id: I9d4dd625441005a36c962628fe3fe1f15ab56bb6
Reviewed-on: https://chromium-review.googlesource.com/c/1328985Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Commit-Queue: Mario Sanchez Prada <mario@igalia.com>
Cr-Commit-Position: refs/heads/master@{#606894}