[Sync] Introduce ModelError for USS error handling.

chrome/browser/sync/test/integration/two_client_uss_sync_test.cc

Index: chrome/browser/sync/test/integration/two_client_uss_sync_test.cc
diff --git a/chrome/browser/sync/test/integration/two_client_uss_sync_test.cc b/chrome/browser/sync/test/integration/two_client_uss_sync_test.cc
index 8a6f76c07573cb945ee6fe683cb90f1595bf8e12..0bba269f2d6d8c54aa2a39db9a5d4b7458ead7d2 100644
--- a/chrome/browser/sync/test/integration/two_client_uss_sync_test.cc
+++ b/chrome/browser/sync/test/integration/two_client_uss_sync_test.cc
@@ -63,14 +63,13 @@ class TestModelTypeSyncBridge : public FakeModelTypeSyncBridge {
 
   TestModelTypeSyncBridge()
       : FakeModelTypeSyncBridge(base::Bind(&ModelTypeChangeProcessor::Create)) {
-    change_processor()->OnMetadataLoaded(syncer::SyncError(),
-                                         db().CreateMetadataBatch());
+    change_processor()->OnMetadataLoaded(db().CreateMetadataBatch());
   }
 
-  syncer::SyncError ApplySyncChanges(
+  syncer::ModelError ApplySyncChanges(
       std::unique_ptr<syncer::MetadataChangeList> metadata_changes,
       syncer::EntityChangeList entity_changes) override {
-    syncer::SyncError error = FakeModelTypeSyncBridge::ApplySyncChanges(
+    syncer::ModelError error = FakeModelTypeSyncBridge::ApplySyncChanges(

[skym, 2017/01/09 18:20:27]

Seems like there should be an #include .../model_error.h in this file. Can you
audit these changes to make sure you didn't miss any others?

[maxbogue, 2017/01/09 21:29:33]

Done.

         std::move(metadata_changes), entity_changes);
     NotifyObservers();
     return error;
@@ -324,7 +323,7 @@ IN_PROC_BROWSER_TEST_F(TwoClientUssSyncTest, Error) {
   ASSERT_TRUE(DataChecker(model1, kKey1, kValue1).Wait());
 
   // Set an error in model 1 to trigger in the next GetUpdates.
-  model1->ErrorOnNextCall(syncer::SyncError::DATATYPE_ERROR);
+  model1->ErrorOnNextCall();
   // Write an item on model 0 to trigger a GetUpdates in model 1.
   model0->WriteItem(kKey1, kValue2);