Force flattening for elements with non-initial value of opacity

third_party/WebKit/Source/core/css/resolver/StyleAdjuster.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 203 matching lines @@
     style.adjustMaskLayers();
 
     // Let the theme also have a crack at adjusting the style.
     if (style.hasAppearance())
         LayoutTheme::theme().adjustStyle(style, element);
 
     // If we have first-letter pseudo style, transitions, or animations, do not share this style.
     if (style.hasPseudoStyle(PseudoIdFirstLetter) || style.transitions() || style.animations())
         style.setUnique();
 
-    // FIXME: when dropping the -webkit prefix on transform-style, we should also have opacity < 1 cause flattening.
-    if (style.preserves3D() && (style.overflowX() != OverflowVisible
-        || style.overflowY() != OverflowVisible
-        || style.hasFilterInducingProperty()))
-        style.setTransformStyle3D(TransformStyle3DFlat);
-
     adjustStyleForEditing(style);
 
     bool isSVGElement = element && element->isSVGElement();
     if (isSVGElement) {
         // Only the root <svg> element in an SVG document fragment tree honors css position
         if (!(isSVGSVGElement(*element) && element->parentNode() && !element->parentNode()->isSVGElement()))
             style.setPosition(ComputedStyle::initialPosition());
 
         // SVG text layout code expects us to be a block-level style element.
         if ((isSVGForeignObjectElement(*element) || isSVGTextElement(*element)) && style.isDisplayInlineType())
@@ skipping 217 matching lines @@
         // We want to count vertical percentage paddings/margins on flex items because our current
         // behavior is different from the spec and we want to gather compatibility data.
         if (style.paddingBefore().hasPercent() || style.paddingAfter().hasPercent())
             UseCounter::count(document, UseCounter::FlexboxPercentagePaddingVertical);
         if (style.marginBefore().hasPercent() || style.marginAfter().hasPercent())
             UseCounter::count(document, UseCounter::FlexboxPercentageMarginVertical);
     }
 }
 
 } // namespace blink