Add support for multiple text decorations with same line positioning

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 93 matching lines @@
 }
 
 // CSS requires text-decoration to be reset at each DOM element for
 // inline blocks, inline tables, shadow DOM crossings, floating elements,
 // and absolute or relatively positioned elements. Outermost <svg> roots are
 // considered to be atomic inline-level.
 static bool doesNotInheritTextDecoration(const ComputedStyle& style, const Element* e)
 {
     return style.display() == INLINE_TABLE
         || style.display() == INLINE_BLOCK || style.display() == INLINE_BOX || isAtShadowBoundary(e)
-        || style.isFloating() || style.hasOutOfFlowPosition() || isOutermostSVGElement(e);
+        || style.isFloating() || style.hasOutOfFlowPosition() || isOutermostSVGElement(e)
+        || isHTMLRTElement(e);
+}
+
+// Certain elements (<a>, <font>) bind strongly to text decoration colors, for legacy reasons.
+static bool overridesTextDecorationColors(const Element* e)
+{
+    return e && (isHTMLFontElement(e) || isHTMLAnchorElement(e));
 }
 
 // FIXME: This helper is only needed because pseudoStyleForElement passes a null
 // element to adjustComputedStyle, so we can't just use element->isInTopLayer().
 static bool isInTopLayer(const Element* element, const ComputedStyle& style)
 {
     return (element && element->isInTopLayer()) || style.styleType() == BACKDROP;
 }
 
 static bool parentStyleForcesZIndexToCreateStackingContext(const ComputedStyle& parentStyle)
@@ skipping 72 matching lines @@
         || style.hasFilter()
         || style.hasBlendMode()
         || style.hasIsolation()
         || style.position() == FixedPosition
         || isInTopLayer(e, style)
         || hasWillChangeThatCreatesStackingContext(style)))
         style.setZIndex(0);
 
     if (doesNotInheritTextDecoration(style, e))
         style.clearAppliedTextDecorations();
-
-    style.applyTextDecorations();
+    style.applyTextDecorations(overridesTextDecorationColors(e));
 
     if (style.overflowX() != OVISIBLE || style.overflowY() != OVISIBLE)
         adjustOverflow(style);
 
     // Cull out any useless layers and also repeat patterns into additional layers.
     style.adjustBackgroundLayers();
     style.adjustMaskLayers();
 
     // Let the theme also have a crack at adjusting the style.
     if (style.hasAppearance())
@@ skipping 265 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);
     }
 }
 
 }