Remove #pragma once from sync

sync/protocol/proto_enum_conversions.h

 // 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.
 
 #ifndef SYNC_PROTOCOL_PROTO_ENUM_CONVERSIONS_H_
 #define SYNC_PROTOCOL_PROTO_ENUM_CONVERSIONS_H_
-#pragma once
 
 // Keep this file in sync with the .proto files in this directory.
 
 #include "sync/protocol/session_specifics.pb.h"
 #include "sync/protocol/sync.pb.h"
 
 // Utility functions to get the string equivalent for some sync proto
 // enums.
 
 namespace syncer {
@@ skipping 23 matching lines @@
 
 const char* GetDeviceTypeString(
     sync_pb::SessionHeader::DeviceType device_type);
 
 const char* GetFaviconTypeString(
     sync_pb::SessionTab::FaviconType favicon_type);
 
 }  // namespace syncer
 
 #endif  // SYNC_PROTOCOL_PROTO_ENUM_CONVERSIONS_H_