Remove custom style building for font-variant-ligatures.

Source/platform/fonts/FontDescription.cpp

 /*
  * Copyright (C) 2007 Nicholas Shanks <contact@nickshanks.com>
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 83 matching lines @@
     }
     ASSERT_NOT_REACHED();
     return FontWeightNormal;
 }
 
 FontTraits FontDescription::traits() const
 {
     return FontTraits(style(), variant(), weight(), stretch());
 }
 
+FontDescription::VariantLigatures FontDescription::variantLigatures() const
+{
+    VariantLigatures ligatures;
+
+    ligatures.common = commonLigaturesState();
+    ligatures.discretionary = discretionaryLigaturesState();
+    ligatures.historical = historicalLigaturesState();
+    ligatures.contextual = contextualLigaturesState();
+
+    return ligatures;
+}
+
 void FontDescription::setTraits(FontTraits traits)
 {
     setStyle(traits.style());
     setVariant(traits.variant());
     setWeight(traits.weight());
     setStretch(traits.stretch());
 }
 
+void FontDescription::setVariantLigatures(const VariantLigatures& ligatures)
+{
+    m_commonLigaturesState = ligatures.common;
+    m_discretionaryLigaturesState = ligatures.discretionary;
+    m_historicalLigaturesState = ligatures.historical;
+    m_contextualLigaturesState = ligatures.contextual;
+
+    updateTypesettingFeatures();
+}
+
 FontDescription FontDescription::makeNormalFeatureSettings() const
 {
     FontDescription normalDescription(*this);
     normalDescription.setFeatureSettings(nullptr);
     return normalDescription;
 }
 
 float FontDescription::effectiveFontSize() const
 {
     float size = (RuntimeEnabledFeatures::subpixelFontScalingEnabled())
@@ skipping 76 matching lines @@
 
         if (discretionaryLigaturesState() == FontDescription::EnabledLigaturesState
             || historicalLigaturesState() == FontDescription::EnabledLigaturesState
             || contextualLigaturesState() == FontDescription::EnabledLigaturesState) {
             m_typesettingFeatures |= blink::Ligatures;
         }
     }
 }
 
 } // namespace blink