Remove custom style building for -webkit-font-feature-settings.

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 a0b47c04dda70aa5305cf0804a0ee968bff1ffc8..e25942f7d5636c7f4f4a1aa29009fa95403d43ab 100644
--- a/Source/core/css/resolver/StyleBuilderConverter.cpp
+++ b/Source/core/css/resolver/StyleBuilderConverter.cpp
@@ -27,6 +27,7 @@
 #include "config.h"
 #include "core/css/resolver/StyleBuilderConverter.h"
 
+#include "core/css/CSSFontFeatureValue.h"
 #include "core/css/CSSFunctionValue.h"
 #include "core/css/CSSGridLineNamesValue.h"
 #include "core/css/CSSPrimitiveValueMappings.h"
@@ -90,6 +91,21 @@ AtomicString StyleBuilderConverter::convertFragmentIdentifier(StyleResolverState
     return nullAtom;
 }
 
+PassRefPtr<FontFeatureSettings> StyleBuilderConverter::convertFontFeatureSettings(StyleResolverState& state, CSSValue* value)
+{
+    if (value->isPrimitiveValue() && toCSSPrimitiveValue(value)->getValueID() == CSSValueNormal)
+        return FontBuilder::initialFeatureSettings();
+
+    CSSValueList* list = toCSSValueList(value);
+    RefPtr<FontFeatureSettings> settings = FontFeatureSettings::create();
+    int len = list->length();
+    for (int i = 0; i < len; ++i) {
+        CSSFontFeatureValue* feature = toCSSFontFeatureValue(list->item(i));
+        settings->append(FontFeature(feature->tag(), feature->value()));
+    }
+    return settings;
+}
+
 FontWeight StyleBuilderConverter::convertFontWeight(StyleResolverState& state, CSSValue* value)
 {
     CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(value);