Remove compiler feature detection for = delete

sky/engine/core/html/HTMLElement.h

Index: sky/engine/core/html/HTMLElement.h
diff --git a/sky/engine/core/html/HTMLElement.h b/sky/engine/core/html/HTMLElement.h
index fb0ef43d7251658c2ddda624732bbd32aeb6193b..65a0c85b05d801587235298baf52672410615c81 100644
--- a/sky/engine/core/html/HTMLElement.h
+++ b/sky/engine/core/html/HTMLElement.h
@@ -67,8 +67,8 @@ protected:
     HTMLElement(const QualifiedName& tagName, Document&, ConstructionType);
 
 private:
-    bool isHTMLElement() const WTF_DELETED_FUNCTION; // This will catch anyone doing an unnecessary check.
-    bool isStyledElement() const WTF_DELETED_FUNCTION; // This will catch anyone doing an unnecessary check.
+    bool isHTMLElement() const = delete; // This will catch anyone doing an unnecessary check.
+    bool isStyledElement() const = delete; // This will catch anyone doing an unnecessary check.
 };
 
 DEFINE_ELEMENT_TYPE_CASTS(HTMLElement, isHTMLElement());