Accept options in history APIs to allow scroll restoration to be disabled

Source/core/loader/HistoryItem.h

Index: Source/core/loader/HistoryItem.h
diff --git a/Source/core/loader/HistoryItem.h b/Source/core/loader/HistoryItem.h
index 661c75ed971a836c276adbec8b4ad4abb04d36c9..829eae8dd7edeef33296d935cbb5a86c711c1a37 100644
--- a/Source/core/loader/HistoryItem.h
+++ b/Source/core/loader/HistoryItem.h
@@ -98,6 +98,9 @@ public:
     void setFrameSequenceNumber(long long number) { m_frameSequenceNumber = number; }
     long long frameSequenceNumber() const { return m_frameSequenceNumber; }
 
+    void setShouldRestoreScroll(bool shouldRestoreScroll) { m_shouldRestoreScroll = shouldRestoreScroll; }
+    bool shouldRestoreScroll() { return m_shouldRestoreScroll; }
+
     void setFormInfoFromRequest(const ResourceRequest&);
     void setFormData(PassRefPtr<FormData>);
     void setFormContentType(const AtomicString&);
@@ -136,6 +139,10 @@ private:
     // one during a history navigation.
     int64_t m_frameSequenceNumber;
 
+    // True if history item should restore scroll position when it is restored
+    // during history traversal.
+    bool m_shouldRestoreScroll;
+
     // Support for HTML5 History
     RefPtr<SerializedScriptValue> m_stateObject;