Added pinch viewport offset to history item.

Source/web/WebViewImpl.h

Index: Source/web/WebViewImpl.h
diff --git a/Source/web/WebViewImpl.h b/Source/web/WebViewImpl.h
index 621e6ca343a26f1fa883cd1b9d912698a1ffcde1..a92f03518cdd1b705a2512d028b9ccf1b38baca8 100644
--- a/Source/web/WebViewImpl.h
+++ b/Source/web/WebViewImpl.h
@@ -189,8 +189,6 @@ public:
     virtual WebFloatPoint pinchViewportOffset() const OVERRIDE;
     virtual float minimumPageScaleFactor() const OVERRIDE;
     virtual float maximumPageScaleFactor() const OVERRIDE;
-    virtual void saveScrollAndScaleState() OVERRIDE;
-    virtual void restoreScrollAndScaleState() OVERRIDE;
     virtual void resetScrollAndScaleState() OVERRIDE;
     virtual void setIgnoreViewportTagScaleLimits(bool) OVERRIDE;
     virtual WebSize contentsPreferredMinimumSize() OVERRIDE;
@@ -627,10 +625,6 @@ private:
 
     PageScaleConstraintsSet m_pageScaleConstraintsSet;
 
-    // Saved page scale state.
-    float m_savedPageScaleFactor; // 0 means that no page scale factor is saved.
-    WebCore::IntSize m_savedScrollOffset;
-
     // The scale moved to by the latest double tap zoom, if any.
     float m_doubleTapZoomPageScaleFactor;
     // Have we sent a double-tap zoom and not yet heard back the scale?