SP: Always anti-alias borders in slimming paint mode.

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 "config.h"
 #include "core/paint/BoxPainter.h"
 
 #include "core/HTMLNames.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLFrameOwnerElement.h"
@@ skipping 855 matching lines @@
 }
 
 bool BoxPainter::paintNinePieceImage(LayoutBoxModelObject& obj, GraphicsContext* graphicsContext, const LayoutRect& rect, const ComputedStyle& style, const NinePieceImage& ninePieceImage, SkXfermode::Mode op)
 {
     NinePieceImagePainter ninePieceImagePainter(obj);
     return ninePieceImagePainter.paint(graphicsContext, rect, style, ninePieceImage, op);
 }
 
 bool BoxPainter::shouldAntialiasLines(GraphicsContext* context)
 {
+    if (RuntimeEnabledFeatures::slimmingPaintEnabled())
+        return true;
     // FIXME: We may want to not antialias when scaled by an integral value,
     // and we may want to antialias when translated by a non-integral value.
     // FIXME: See crbug.com/382491. getCTM does not include scale factors applied at raster time, such
     // as device zoom.
     return !context->getCTM().isIdentityOrTranslationOrFlipped();
 }
 
 bool BoxPainter::allCornersClippedOut(const FloatRoundedRect& border, const IntRect& intClipRect)
 {
     LayoutRect boundingRect(border.rect());
@@ skipping 156 matching lines @@
                 else
                     clippedEdges |= GraphicsContext::BottomEdge;
             }
             // TODO: support non-integer shadows - crbug.com/334828
             context->drawInnerShadow(border, shadowColor, flooredIntSize(shadowOffset), shadowBlur, shadowSpread, clippedEdges);
         }
     }
 }
 
 } // namespace blink