Remove WebHistoryItem child usage

content/renderer/history_serialization.h

 // Copyright 2014 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 CONTENT_RENDERER_HISTORY_SERIALIZATION_H_
 #define CONTENT_RENDERER_HISTORY_SERIALIZATION_H_
 
 #include <string>
 
 #include "content/common/content_export.h"
 
 namespace blink {
 class WebHistoryItem;
 }
 
 namespace content {
+class HistoryEntry;
 class PageState;
 
-CONTENT_EXPORT PageState HistoryItemToPageState(
+CONTENT_EXPORT PageState HistoryEntryToPageState(HistoryEntry* entry);
+CONTENT_EXPORT PageState SingleHistoryItemToPageState(
     const blink::WebHistoryItem& item);
-CONTENT_EXPORT blink::WebHistoryItem PageStateToHistoryItem(
-    const PageState& state);
+CONTENT_EXPORT HistoryEntry* PageStateToHistoryEntry(const PageState& state);
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_HISTORY_SERIALIZATION_H_