Downgrade error to warning for new policy entry in PolicyMigrator

This matches the behavior of RemapRenamedPolices function in
PolicyServiceImpl

Change-Id: I7a38bb6f286c6ae873373454e379ec4103cbf58c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2636278
Commit-Queue: Julian Pastarmov <pastarmovj@chromium.org>
Reviewed-by: Julian Pastarmov <pastarmovj@chromium.org>
Auto-Submit: Owen Min <zmin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#844728}

chrome/browser/policy/chrome_extension_policy_migrator_unittest.cc

@@ -114,7 +114,7 @@ TEST(ChromeExtensionPolicyMigratorTest, DeprecatedWarnings) {
   base::RepeatingCallback<base::string16(int)> l10nlookup =
       base::BindRepeating(&l10n_util::GetStringUTF16);
   EXPECT_FALSE(
-      chrome_map.Get(kNewPolicy1)->GetLocalizedErrors(l10nlookup).empty());
+      chrome_map.Get(kNewPolicy1)->GetLocalizedWarnings(l10nlookup).empty());
 }
 
 }  // namespace policy

components/policy/core/common/legacy_chrome_policy_migrator_unittest.cc

@@ -60,7 +60,7 @@ TEST(LegacyChromePolicyMigratorTest, CopyPolicyIfUnset) {
   EXPECT_FALSE(
       chrome_map.Get(kOldPolicy)->GetLocalizedErrors(l10nlookup).empty());
   EXPECT_FALSE(
-      chrome_map.Get(kNewPolicy)->GetLocalizedErrors(l10nlookup).empty());
+      chrome_map.Get(kNewPolicy)->GetLocalizedWarnings(l10nlookup).empty());
 }
 
 TEST(LegacyChromePolicyMigratorTest, TransformPolicy) {
@@ -100,6 +100,8 @@ TEST(LegacyChromePolicyMigratorTest, IgnoreOldIfNewIsSet) {
   EXPECT_FALSE(
       chrome_map.Get(kOldPolicy)->GetLocalizedErrors(l10nlookup).empty());
   // No warnings on new policy because it was unchanged.
+  EXPECT_TRUE(
+      chrome_map.Get(kNewPolicy)->GetLocalizedWarnings(l10nlookup).empty());
   EXPECT_TRUE(
       chrome_map.Get(kNewPolicy)->GetLocalizedErrors(l10nlookup).empty());
 }

components/policy/core/common/policy_migrator.cc

@@ -33,8 +33,8 @@ void PolicyMigrator::CopyPolicyIfUnset(PolicyMap& source,
               << "' has been copied to '" << migration.new_name << "'.";
       auto new_entry = entry->DeepCopy();
       migration.transform.Run(new_entry.value());
-      new_entry.AddError(IDS_POLICY_MIGRATED_NEW_POLICY,
-                         {base::UTF8ToUTF16(migration.old_name)});
+      new_entry.AddWarning(IDS_POLICY_MIGRATED_NEW_POLICY,
+                           {base::UTF8ToUTF16(migration.old_name)});
       dest->Set(migration.new_name, std::move(new_entry));
     } else {
       VLOG(3) << "Legacy policy '" << migration.old_name