[s13n] Port enterprise_platform_keys_private_api_unittest.cc way from SigninManager

... in favor of identity testing utils.

SigninManager is going to be an implementation detail of IdentityManager. This CL
is a straightforward move between the two APIs.


Change-Id: I4372b7c81fdd229ea6a7b34b67b2c32d03e00c92
Reviewed-on: https://chromium-review.googlesource.com/c/1405728
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Toni Baržić <tbarzic@chromium.org>
Commit-Queue: Antonio Gomes <tonikitoo@igalia.com>
Cr-Commit-Position: refs/heads/master@{#622290}
1 file changed