Test [[IsHTMLDDA]] object with `typeof` operator (#2706)

test/annexB/language/expressions/typeof/emulates-undefined.js

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+// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-IsHTMLDDA-internal-slot-typeof
+description: >
+  `typeof` operator returns "undefined" for [[IsHTMLDDA]] object.
+info: |
+  Changes to the typeof Operator
+
+  The following table entry is inserted into Table 35 immediately
+  preceeding the entry for "Object (implements [[Call]])":
+
+  Type of val: Object (has an [[IsHTMLDDA]] internal slot)
+  Result: "undefined"
+features: [IsHTMLDDA]
+---*/
+
+var IsHTMLDDA = $262.IsHTMLDDA;
+
+assert(typeof IsHTMLDDA === "undefined", '=== "undefined"');
+assert.sameValue(typeof IsHTMLDDA, "undefined");
+
+assert(typeof IsHTMLDDA !== "object", '!== "object"');
+assert.sameValue(typeof IsHTMLDDA === "object", false, '!== "object"');
+
+assert(typeof IsHTMLDDA !== "function", '!== "function"');
+assert.sameValue(typeof IsHTMLDDA === "function", false, '!== "function"');