Remove some unnecessary and precision-losing pixel snapping code.

Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 1152 matching lines @@
 
 void LayoutBox::paintBoxDecorationBackground(const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     BoxPainter(*this).paintBoxDecorationBackground(paintInfo, paintOffset);
 }
 
 
 bool LayoutBox::getBackgroundPaintedExtent(LayoutRect& paintedExtent)
 {
     ASSERT(hasBackground());
-    LayoutRect backgroundRect = pixelSnappedIntRect(borderBoxRect());

[chrishtr, 2015/02/25 18:28:40]

This one is not necessary because borderBoxRect() always uses a top-left
position of (0,0).

+    LayoutRect backgroundRect = borderBoxRect();
 
     Color backgroundColor = resolveColor(CSSPropertyBackgroundColor);
     if (backgroundColor.alpha()) {
         paintedExtent = backgroundRect;
         return true;
     }
 
     if (!style()->backgroundLayers().image() || style()->backgroundLayers().next()) {
         paintedExtent =  backgroundRect;
         return true;
@@ skipping 3443 matching lines @@
 }
 
 void LayoutBox::invalidateDisplayItemClients(DisplayItemList* displayItemList) const
 {
     LayoutBoxModelObject::invalidateDisplayItemClients(displayItemList);
     if (LayerScrollableArea* area = scrollableArea())
         displayItemList->invalidate(area->displayItemClient());
 }
 
 } // namespace blink