Migrated policies should have a warning instead of an error

Inclusive policies that have values because their older deprecated
value has been migrated programmatically should not be in error, they
should be in a warning state.

Visual: http://screen/4XmySdAwkiTuor5

Bug: 1033069
Change-Id: I48a481ef60207516102f739a942a8c12093a980c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2611548Reviewed-by: Julian Pastarmov <pastarmovj@chromium.org>
Commit-Queue: Yann Dago <ydago@chromium.org>
Cr-Commit-Position: refs/heads/master@{#841157}

components/policy/core/common/policy_service_impl.cc

@@ -143,8 +143,8 @@ void RemapRenamedPolicies(PolicyMap* policies) {
     if (old_policy &&
         (!new_policy || old_policy->has_higher_priority_than(*new_policy))) {
       PolicyMap::Entry policy_entry = old_policy->DeepCopy();
-      policy_entry.AddError(IDS_POLICY_MIGRATED_NEW_POLICY,
-                            {base::UTF8ToUTF16(policy_pair.first)});
+      policy_entry.AddWarning(IDS_POLICY_MIGRATED_NEW_POLICY,
+                              {base::UTF8ToUTF16(policy_pair.first)});
       old_policy->AddError(IDS_POLICY_MIGRATED_OLD_POLICY,
                            {base::UTF8ToUTF16(policy_pair.second)});
       policies->Set(policy_pair.second, std::move(policy_entry));