[Sync] Migrate bridge implementations to change list based MergeSyncData

components/sync/model/fake_model_type_sync_bridge.cc

 // Copyright 2015 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/model/fake_model_type_sync_bridge.h"
 
 #include <set>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 214 matching lines @@
     if (remote_storage_keys.find(kv.first) == remote_storage_keys.end()) {
       change_processor()->Put(kv.first, CopyEntityData(*kv.second),
                               metadata_change_list.get());
     }
   }
 
   ApplyMetadataChangeList(std::move(metadata_change_list));
   return {};
 }
 
-base::Optional<ModelError> FakeModelTypeSyncBridge::MergeSyncData(
-    std::unique_ptr<MetadataChangeList> metadata_change_list,
-    EntityDataMap entity_data) {
-  NOTREACHED();
-  return {};
-}
-
 base::Optional<ModelError> FakeModelTypeSyncBridge::ApplySyncChanges(
     std::unique_ptr<MetadataChangeList> metadata_changes,
     EntityChangeList entity_changes) {
   if (error_next_) {
     error_next_ = false;
     return ModelError(FROM_HERE, "boom");
   }
 
   for (const EntityChange& change : entity_changes) {
     switch (change.type()) {
@@ skipping 131 matching lines @@
   new_data->id = old_data.id;
   new_data->client_tag_hash = old_data.client_tag_hash;
   new_data->non_unique_name = old_data.non_unique_name;
   new_data->specifics = old_data.specifics;
   new_data->creation_time = old_data.creation_time;
   new_data->modification_time = old_data.modification_time;
   return new_data;
 }
 
 }  // namespace syncer