Preserve fractional scroll offset for JS scrolling API

Source/core/frame/LocalFrame.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Simon Hausmann <hausmann@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  *                     2001 George Staikos <staikos@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov <ap@nypop.com>
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
@@ skipping 543 matching lines @@
     if (document->isSVGDocument()) {
         if (!document->accessSVGExtensions().zoomAndPanEnabled())
             return;
     }
 
     if (m_pageZoomFactor != pageZoomFactor) {
         if (FrameView* view = this->view()) {
             // Update the scroll position when doing a full page zoom, so the content stays in relatively the same position.
             LayoutPoint scrollPosition = view->scrollPosition();
             float percentDifference = (pageZoomFactor / m_pageZoomFactor);
-            view->setScrollPosition(IntPoint(scrollPosition.x() * percentDifference, scrollPosition.y() * percentDifference));
+            view->setScrollPosition(DoublePoint(scrollPosition.x() * percentDifference, scrollPosition.y() * percentDifference));
         }
     }
 
     m_pageZoomFactor = pageZoomFactor;
     m_textZoomFactor = textZoomFactor;
 
     for (RefPtrWillBeRawPtr<Frame> child = tree().firstChild(); child; child = child->tree().nextSibling()) {
         if (child->isLocalFrame())
             toLocalFrame(child.get())->setPageAndTextZoomFactors(m_pageZoomFactor, m_textZoomFactor);
     }
@@ skipping 166 matching lines @@
 
     return curFrame;
 }
 
 void LocalFrame::setPagePopupOwner(Element& owner)
 {
     m_pagePopupOwner = &owner;
 }
 
 } // namespace blink