GitLab

Call CloudPolicyService::RefreshPolicy instead of
CloudPolicyClient::FetchPolicy in CloudPolicyRefreshScheduler, so there
is a common path for in session policy fetches.
It allows to add additional logic for policy fetch to CloudPolicyService.
It is a part of larger change: passing credentials with child user policy
fetch.

Bug: 839025
Test: CloudPolicyRefreshSchedulerTest + manually
Change-Id: I3f5b497ef28179d3d181d45b30bf11b4a4f3fcac
Reviewed-on: https://chromium-review.googlesource.com/c/1339099
Commit-Queue: Aga Wronska <agawronska@chromium.org>
Reviewed-by: Pavol Marko <pmarko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609883}