Use LayoutUnit::fromFloatRound for setting scroll values

Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 671 matching lines @@
 
     return 0;
 }
 
 void Element::setScrollLeft(int newLeft)
 {
     document().updateLayoutIgnorePendingStylesheets();
 
     if (document().documentElement() != this) {
         if (RenderBox* rend = renderBox())
-            rend->setScrollLeft(roundf(newLeft * rend->style()->effectiveZoom()));
+            rend->setScrollLeft(LayoutUnit::fromFloatRound(newLeft * rend->style()->effectiveZoom()));
         return;
     }
 
     if (RuntimeEnabledFeatures::scrollTopLeftInteropEnabled()) {
         if (document().inQuirksMode())
             return;
 
         LocalFrame* frame = document().frame();
         if (!frame)
             return;
@@ skipping 25 matching lines @@
     // FIXME: Use scrollBehavior to decide whether to scroll smoothly or instantly.
     setScrollLeft(position);
 }
 
 void Element::setScrollTop(int newTop)
 {
     document().updateLayoutIgnorePendingStylesheets();
 
     if (document().documentElement() != this) {
         if (RenderBox* rend = renderBox())
-            rend->setScrollTop(roundf(newTop * rend->style()->effectiveZoom()));
+            rend->setScrollTop(LayoutUnit::fromFloatRound(newTop * rend->style()->effectiveZoom()));
         return;
     }
 
     if (RuntimeEnabledFeatures::scrollTopLeftInteropEnabled()) {
         if (document().inQuirksMode())
             return;
 
         LocalFrame* frame = document().frame();
         if (!frame)
             return;
@@ skipping 2619 matching lines @@
 {
 #if ENABLE(OILPAN)
     if (hasRareData())
         visitor->trace(elementRareData());
     visitor->trace(m_elementData);
 #endif
     ContainerNode::trace(visitor);
 }
 
 } // namespace WebCore