Read and restore persisted slice info

components/history/content/browser/download_database_helper.h

Index: components/history/content/browser/download_database_helper.h
diff --git a/components/history/content/browser/download_database_helper.h b/components/history/content/browser/download_database_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..a3a6a84325a2d883ebf8b9469ce2c3def0317f71
--- /dev/null
+++ b/components/history/content/browser/download_database_helper.h
@@ -0,0 +1,20 @@
+// Copyright 2017 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_HISTORY_CONTENT_BROWSER_DOWNLOAD_DATABASE_HELPER_H_
+#define COMPONENTS_HISTORY_CONTENT_BROWSER_DOWNLOAD_DATABASE_HELPER_H_
+
+#include <vector>
+
+#include "components/history/core/browser/download_slice_info.h"
+#include "content/public/browser/download_item.h"
+
+namespace history {
+
+std::vector<content::DownloadItem::ReceivedSlice> ToContentReceivedSlices(
+    const std::vector<DownloadSliceInfo>& info);
+
+}  // namespace history
+
+#endif  // COMPONENTS_HISTORY_CONTENT_BROWSER_DOWNLOAD_DATABASE_HELPER_H_