[Sync] Fixing easy lint violations.

components/sync/core/write_node.cc

 // Copyright (c) 2012 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/core/write_node.h"
 
+#include <memory>
+
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "components/sync/base/cryptographer.h"
 #include "components/sync/core/base_transaction.h"
 #include "components/sync/core/write_transaction.h"
 #include "components/sync/core_impl/syncapi_internal.h"
 #include "components/sync/protocol/bookmark_specifics.pb.h"
 #include "components/sync/protocol/typed_url_specifics.pb.h"
 #include "components/sync/syncable/mutable_entry.h"
@@ skipping 450 matching lines @@
   syncable::Id predecessor_id =
       predecessor ? predecessor->GetSyncId() : syncable::Id();
   return entry_->PutPredecessor(predecessor_id);
 }
 
 void WriteNode::MarkForSyncing() {
   syncable::MarkForSyncing(entry_);
 }
 
 }  // namespace syncer