Modify sync unit test to use standard sql::test:: helper.

components/sync/test/directory_backing_store_corruption_testing.h

-// 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.
-
-#ifndef COMPONENTS_SYNC_TEST_DIRECTORY_BACKING_STORE_CORRUPTION_TESTING_H_
-#define COMPONENTS_SYNC_TEST_DIRECTORY_BACKING_STORE_CORRUPTION_TESTING_H_
-
-#include "base/files/file_path.h"
-
-namespace syncer {
-namespace syncable {
-namespace corruption_testing {
-
-// The number of DB entries required to reliably trigger detectable corruption
-// using |CorruptDatabase|.
-extern const int kNumEntriesRequiredForCorruption;
-
-// Corrupt the sync database at |backing_file_path|.
-//
-// Returns true if the database was successfully corrupted.
-bool CorruptDatabase(const base::FilePath& backing_file_path);
-
-}  // namespace corruption_testing
-}  // namespace syncable
-}  // namespace syncer
-
-#endif  // COMPONENTS_SYNC_TEST_DIRECTORY_BACKING_STORE_CORRUPTION_TESTING_H_