CSSValue Immediates: Change CSSValue to an object instead of a pointer

Source/core/layout/svg/ReferenceFilterBuilder.cpp

Index: Source/core/layout/svg/ReferenceFilterBuilder.cpp
diff --git a/Source/core/layout/svg/ReferenceFilterBuilder.cpp b/Source/core/layout/svg/ReferenceFilterBuilder.cpp
index dc4d3032acb910b6e92bb92c2c72051f936ccd93..f3bfcd1e67e16b3790695121b0982b726575d54a 100644
--- a/Source/core/layout/svg/ReferenceFilterBuilder.cpp
+++ b/Source/core/layout/svg/ReferenceFilterBuilder.cpp
@@ -76,10 +76,10 @@ static EColorInterpolation colorInterpolationForElement(SVGElement& element, ECo
     // No layout has been performed, try to determine the property value
     // "manually" (used by external SVG files.)
     if (const StylePropertySet* propertySet = element.presentationAttributeStyle()) {
-        RefPtrWillBeRawPtr<CSSValue> cssValue = propertySet->getPropertyCSSValue(CSSPropertyColorInterpolationFilters);
+        NullableCSSValue cssValue = propertySet->getPropertyCSSValue(CSSPropertyColorInterpolationFilters);
         if (cssValue && cssValue->isPrimitiveValue()) {
-            const CSSPrimitiveValue& primitiveValue = *((CSSPrimitiveValue*)cssValue.get());
-            return static_cast<EColorInterpolation>(primitiveValue);
+            const CSSPrimitiveValue* primitiveValue = toCSSPrimitiveValue(cssValue);
+            return static_cast<EColorInterpolation>(*primitiveValue);
         }
     }
     // 'auto' is the default (per Filter Effects), but since the property is