Remove custom style building for font-variant-ligatures.

Source/core/css/resolver/StyleBuilderConverter.cpp

Index: Source/core/css/resolver/StyleBuilderConverter.cpp
diff --git a/Source/core/css/resolver/StyleBuilderConverter.cpp b/Source/core/css/resolver/StyleBuilderConverter.cpp
index f8ed6d37572dba2bb447176a8a72f9b6c53e31be..54b86566976329a1038fc5cba804da0cba0a071c 100644
--- a/Source/core/css/resolver/StyleBuilderConverter.cpp
+++ b/Source/core/css/resolver/StyleBuilderConverter.cpp
@@ -90,6 +90,52 @@ AtomicString StyleBuilderConverter::convertFragmentIdentifier(StyleResolverState
     return nullAtom;
 }
 
+FontDescription::VariantLigatures StyleBuilderConverter::convertFontVariantLigatures(StyleResolverState&, CSSValue* value)
+{
+    if (value->isValueList()) {
+        FontDescription::VariantLigatures ligatures;
+        CSSValueList* valueList = toCSSValueList(value);
+        for (size_t i = 0; i < valueList->length(); ++i) {
+            CSSValue* item = valueList->item(i);
+            CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(item);
+            switch (primitiveValue->getValueID()) {
+            case CSSValueNoCommonLigatures:
+                ligatures.common = FontDescription::DisabledLigaturesState;
+                break;
+            case CSSValueCommonLigatures:
+                ligatures.common = FontDescription::EnabledLigaturesState;
+                break;
+            case CSSValueNoDiscretionaryLigatures:
+                ligatures.discretionary = FontDescription::DisabledLigaturesState;
+                break;
+            case CSSValueDiscretionaryLigatures:
+                ligatures.discretionary = FontDescription::EnabledLigaturesState;
+                break;
+            case CSSValueNoHistoricalLigatures:
+                ligatures.historical = FontDescription::DisabledLigaturesState;
+                break;
+            case CSSValueHistoricalLigatures:
+                ligatures.historical = FontDescription::EnabledLigaturesState;
+                break;
+            case CSSValueNoContextual:
+                ligatures.contextual = FontDescription::DisabledLigaturesState;
+                break;
+            case CSSValueContextual:
+                ligatures.contextual = FontDescription::EnabledLigaturesState;
+                break;
+            default:
+                ASSERT_NOT_REACHED();
+                break;
+            }
+        }
+        return ligatures;
+    }
+
+    ASSERT_WITH_SECURITY_IMPLICATION(value->isPrimitiveValue());
+    ASSERT(toCSSPrimitiveValue(value)->getValueID() == CSSValueNormal);
+    return FontDescription::VariantLigatures();
+}
+
 EGlyphOrientation StyleBuilderConverter::convertGlyphOrientation(StyleResolverState&, CSSValue* value)
 {
     if (!value->isPrimitiveValue())