Avoid using transparency layer for fancy borders.

Source/core/rendering/RenderBox.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 1186 matching lines @@
     if (contextScaling.width() > 1)
         contextScaling.setWidth(1);
     if (contextScaling.height() > 1)
         contextScaling.setHeight(1);
 
     if (borderObscuresBackgroundEdge(contextScaling))
         return BackgroundBleedShrinkBackground;
     if (!style->hasAppearance() && borderObscuresBackground() && backgroundHasOpaqueTopLayer())
         return BackgroundBleedBackgroundOverBorder;
 
-    return BackgroundBleedUseTransparencyLayer;
+    return BackgroundBleedClipBackground;
 }
 
 void RenderBox::paintBoxDecorations(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     if (!paintInfo.shouldPaintWithinRoot(this))
         return;
 
     LayoutRect paintRect = borderBoxRect();
     paintRect.moveBy(paintOffset);
     paintBoxDecorationsWithRect(paintInfo, paintOffset, paintRect);
 }
 
 void RenderBox::paintBoxDecorationsWithRect(PaintInfo& paintInfo, const LayoutPoint& paintOffset, const LayoutRect& paintRect)
 {
     BackgroundBleedAvoidance bleedAvoidance = determineBackgroundBleedAvoidance(paintInfo.context);
 
     // FIXME: Should eventually give the theme control over whether the box shadow should paint, since controls could have
     // custom shadows of their own.
     if (!boxShadowShouldBeAppliedToBackground(bleedAvoidance))
         paintBoxShadow(paintInfo, paintRect, style(), Normal);
 
     GraphicsContextStateSaver stateSaver(*paintInfo.context, false);
-    if (bleedAvoidance == BackgroundBleedUseTransparencyLayer) {
-        // To avoid the background color bleeding out behind the border, we'll render background and border
-        // into a transparency layer, and then clip that in one go (which requires setting up the clip before
-        // beginning the layer).
+    if (bleedAvoidance == BackgroundBleedClipBackground) {
+        stateSaver.save();
         RoundedRect border = style()->getRoundedBorderFor(paintRect);
-        stateSaver.save();
         paintInfo.context->clipRoundedRect(border);
-        paintInfo.context->beginTransparencyLayer(1);
     }
 
     paintBackgroundWithBorderAndBoxShadow(paintInfo, paintRect, bleedAvoidance);
-
-    if (bleedAvoidance == BackgroundBleedUseTransparencyLayer)
-        paintInfo.context->endLayer();
 }
 
 void RenderBox::paintBackgroundWithBorderAndBoxShadow(PaintInfo& paintInfo, const LayoutRect& paintRect, BackgroundBleedAvoidance bleedAvoidance)
 {
     // If we have a native theme appearance, paint that before painting our background.
     // The theme will tell us whether or not we should also paint the CSS background.
     IntRect snappedPaintRect(pixelSnappedIntRect(paintRect));
     bool themePainted = style()->hasAppearance() && !RenderTheme::theme().paint(this, paintInfo, snappedPaintRect);
     if (!themePainted) {
         if (bleedAvoidance == BackgroundBleedBackgroundOverBorder)
@@ skipping 3445 matching lines @@
         return 0;
 
     if (!layoutState && !flowThreadContainingBlock())
         return 0;
 
     RenderBlock* containerBlock = containingBlock();
     return containerBlock->offsetFromLogicalTopOfFirstPage() + logicalTop();
 }
 
 } // namespace WebCore