[SyncFS] Clean up V1 drive_file_sync_util.h dependency from V2

chrome/browser/sync_file_system/drive_backend/drive_backend_util.h

Index: chrome/browser/sync_file_system/drive_backend/drive_backend_util.h
diff --git a/chrome/browser/sync_file_system/drive_backend/drive_backend_util.h b/chrome/browser/sync_file_system/drive_backend/drive_backend_util.h
index 0515a005a3344e17b42d0ddd890f0af2287c9309..5c30d6ab957b65b8de6760439860e5de750ffbf7 100644
--- a/chrome/browser/sync_file_system/drive_backend/drive_backend_util.h
+++ b/chrome/browser/sync_file_system/drive_backend/drive_backend_util.h
@@ -10,6 +10,8 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "chrome/browser/sync_file_system/drive_backend/metadata_database.pb.h"
+#include "chrome/browser/sync_file_system/sync_status_code.h"
+#include "google_apis/drive/gdata_errorcode.h"
 #include "webkit/common/blob/scoped_file.h"
 
 namespace google_apis {
@@ -56,6 +58,9 @@ std::string GetMimeTypeFromTitle(const base::FilePath& title);
 scoped_ptr<google_apis::ResourceEntry> GetOldestCreatedFolderResource(
     ScopedVector<google_apis::ResourceEntry> list);
 
+SyncStatusCode GDataErrorCodeToSyncStatusCode(
+    google_apis::GDataErrorCode error);
+
 }  // namespace drive_backend
 }  // namespace sync_file_system