Adjust the rounding methodology for tiled background phase

third_party/WebKit/Source/core/paint/BoxPainter.cpp

 // 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.
 
 #include "core/paint/BoxPainter.h"
 
 #include "core/HTMLNames.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/layout/ImageQualityController.h"
@@ skipping 433 matching lines @@
         }
     }
 
     // no progressive loading of the background image
     if (shouldPaintBackgroundImage) {
         if (!geometry.destRect().isEmpty()) {
             SkXfermode::Mode bgOp = WebCoreCompositeToSkiaComposite(bgLayer.composite(), bgLayer.blendMode());
             // if op != SkXfermode::kSrcOver_Mode, a mask is being painted.
             SkXfermode::Mode compositeOp = op == SkXfermode::kSrcOver_Mode ? bgOp : op;
             const LayoutObject* clientForBackgroundImage = backgroundObject ? backgroundObject : &obj;
-            RefPtr<Image> image = bgImage->image(clientForBackgroundImage, flooredIntSize(geometry.imageContainerSize()), obj.style()->effectiveZoom());
+            RefPtr<Image> image = bgImage->image(clientForBackgroundImage, flooredIntSize(geometry.tileSize()), obj.style()->effectiveZoom());
             InterpolationQuality interpolationQuality = chooseInterpolationQuality(*clientForBackgroundImage, image.get(), &bgLayer, LayoutSize(geometry.tileSize()));
             if (bgLayer.maskSourceType() == MaskLuminance)
                 context.setColorFilter(ColorFilterLuminanceToAlpha);
             InterpolationQuality previousInterpolationQuality = context.imageInterpolationQuality();
             context.setImageInterpolationQuality(interpolationQuality);
             TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "PaintImage", "data", InspectorPaintImageEvent::data(obj, *bgImage));
             context.drawTiledImage(image.get(), FloatRect(geometry.destRect()), FloatPoint(geometry.phase()), FloatSize(geometry.tileSize()),
                 compositeOp, FloatSize(geometry.spaceSize()));
             context.setImageInterpolationQuality(previousInterpolationQuality);
         }
@@ skipping 227 matching lines @@
     }
 }
 
 bool BoxPainter::shouldForceWhiteBackgroundForPrintEconomy(const ComputedStyle& style, const Document& document)
 {
     return document.printing() && style.getPrintColorAdjust() == PrintColorAdjustEconomy
         && (!document.settings() || !document.settings()->shouldPrintBackgrounds());
 }
 
 } // namespace blink