LibWeb+WebContent: Change the "noopener" storage type to a named enum

Userland/Libraries/LibWeb/HTML/TokenizedFeatures.h

@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+namespace Web::HTML::TokenizedFeature {
+
+#define TOKENIZED_FEATURE(Feature) \
+    enum class Feature {           \
+        Yes,                       \
+        No,                        \
+    }
+
+TOKENIZED_FEATURE(NoOpener);
+
+}