[s13n] Migrate the IdentityTestEnvironmentProfileAdaptor clients that pass PrefService to use Builder variant

The "build variant" is more powerful, than the one that takes a |prefs|
as parameter.

TBR=emaxx@chromium.org (chrome/browser/policy/cloud/user_policy_signin_service_unittest.cc)

BUG=905687

Change-Id: I622446888ad8e31ef3fd0d464ac5ab25375abf3c
Reviewed-on: https://chromium-review.googlesource.com/c/1340889
Commit-Queue: Antonio Gomes <tonikitoo@igalia.com>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609669}