Make body element background image use correct interpolation quality.

Source/core/paint/BoxPainter.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BoxPainter_h
 #define BoxPainter_h
 
 #include "core/layout/LayoutBoxModelObject.h"
 #include "core/paint/ObjectPainter.h"
 
@@ skipping 12 matching lines @@
     void paint(const PaintInfo&, const LayoutPoint&);
 
     void paintBoxDecorationBackground(const PaintInfo&, const LayoutPoint&);
     void paintMask(const PaintInfo&, const LayoutPoint&);
     void paintClippingMask(const PaintInfo&, const LayoutPoint&);
     void paintFillLayers(const PaintInfo&, const Color&, const FillLayer&, const LayoutRect&, BackgroundBleedAvoidance = BackgroundBleedNone, SkXfermode::Mode = SkXfermode::kSrcOver_Mode, LayoutObject* backgroundObject = 0);
     void paintMaskImages(const PaintInfo&, const LayoutRect&);
     void paintBoxDecorationBackgroundWithRect(const PaintInfo&, const LayoutPoint&, const LayoutRect&);
     static void paintFillLayerExtended(LayoutBoxModelObject&, const PaintInfo&, const Color&, const FillLayer&, const LayoutRect&, BackgroundBleedAvoidance, InlineFlowBox* = 0, const LayoutSize& = LayoutSize(), SkXfermode::Mode = SkXfermode::kSrcOver_Mode, LayoutObject* backgroundObject = 0, bool skipBaseColor = false);
     static void calculateBackgroundImageGeometry(LayoutBoxModelObject&, const LayoutBoxModelObject* paintContainer, const FillLayer&, const LayoutRect& paintRect, BackgroundImageGeometry&, LayoutObject* = 0);
-    static InterpolationQuality chooseInterpolationQuality(LayoutBoxModelObject&, GraphicsContext*, Image*, const void*, const LayoutSize&);
+    static InterpolationQuality chooseInterpolationQuality(LayoutObject&, GraphicsContext*, Image*, const void*, const LayoutSize&);
     static bool paintNinePieceImage(LayoutBoxModelObject&, GraphicsContext*, const LayoutRect&, const LayoutStyle&, const NinePieceImage&, SkXfermode::Mode = SkXfermode::kSrcOver_Mode);
     static void paintBorder(LayoutBoxModelObject&, const PaintInfo&, const LayoutRect&, const LayoutStyle&, BackgroundBleedAvoidance = BackgroundBleedNone, bool includeLogicalLeftEdge = true, bool includeLogicalRightEdge = true);
     static void paintBoxShadow(const PaintInfo&, const LayoutRect&, const LayoutStyle&, ShadowStyle, bool includeLogicalLeftEdge = true, bool includeLogicalRightEdge = true);
     static bool shouldAntialiasLines(GraphicsContext*);
 
 private:
     void paintBackground(const PaintInfo&, const LayoutRect&, const Color& backgroundColor, BackgroundBleedAvoidance = BackgroundBleedNone);
     void paintRootBoxFillLayers(const PaintInfo&);
     void paintFillLayer(const PaintInfo&, const Color&, const FillLayer&, const LayoutRect&, BackgroundBleedAvoidance, SkXfermode::Mode, LayoutObject* backgroundObject, bool skipBaseColor = false);
     static void paintRootBackgroundColor(LayoutObject&, const PaintInfo&, const LayoutRect&, const Color&);
@@ skipping 23 matching lines @@
     LayoutRect boundsForDrawingRecorder(const LayoutPoint& paintOffset);
     LayoutRect scrolledBackgroundRect();
 
     // FIXME: this should be const.
     LayoutBox& m_layoutBox;
 };
 
 } // namespace blink
 
 #endif