[Sync] Sanity test for UserEvents.

components/sync/test/fake_server/fake_server.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/sync/test/fake_server/fake_server.h"
 
 #include <algorithm>
 #include <limits>
 #include <set>
 #include <utility>
@@ skipping 352 matching lines @@
 string FakeServer::CommitEntity(
     const sync_pb::SyncEntity& client_entity,
     sync_pb::CommitResponse_EntryResponse* entry_response,
     const string& client_guid,
     const string& parent_id) {
   if (client_entity.version() == 0 && client_entity.deleted()) {
     return string();
   }
 
   std::unique_ptr<FakeServerEntity> entity;
+  syncer::ModelType type = GetModelType(client_entity);
   if (client_entity.deleted()) {
     entity = TombstoneEntity::Create(client_entity.id_string(),
                                      client_entity.client_defined_unique_tag());
     DeleteChildren(client_entity.id_string());
-  } else if (GetModelType(client_entity) == syncer::NIGORI) {
+  } else if (type == syncer::NIGORI) {
     // NIGORI is the only permanent item type that should be updated by the
     // client.
     EntityMap::const_iterator iter = entities_.find(client_entity.id_string());
     CHECK(iter != entities_.end());
     entity = PermanentEntity::CreateUpdatedNigoriEntity(client_entity,
                                                         *iter->second);
-  } else if (client_entity.has_client_defined_unique_tag()) {
-    entity = UniqueClientEntity::Create(client_entity);
-  } else {
+  } else if (type == syncer::BOOKMARKS) {
     // TODO(pvalenzuela): Validate entity's parent ID.
     EntityMap::const_iterator iter = entities_.find(client_entity.id_string());
     if (iter != entities_.end()) {
       entity = BookmarkEntity::CreateUpdatedVersion(client_entity,
                                                     *iter->second, parent_id);
     } else {
       entity = BookmarkEntity::CreateNew(client_entity, parent_id, client_guid);
     }
-  }
-
-  if (!entity) {
-    // TODO(pvalenzuela): Add logging so that it is easier to determine why
-    // creation failed.
-    return string();
+  } else {
+    entity = UniqueClientEntity::Create(client_entity);
   }
 
   const std::string id = entity->id();
   SaveEntity(std::move(entity));
   BuildEntryResponseForSuccessfulCommit(id, entry_response);
   return id;
 }
 
 void FakeServer::BuildEntryResponseForSuccessfulCommit(
     const std::string& entity_id,
@@ skipping 290 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
   return weak_ptr_factory_.GetWeakPtr();
 }
 
 std::string FakeServer::GetStoreBirthday() const {
   DCHECK(thread_checker_.CalledOnValidThread());
   return base::Int64ToString(store_birthday_);
 }
 
 }  // namespace fake_server