Bug 1353197 - Add a test for URLSearchParams handling of non-ASCII keys in the record<> ctor, r=annevk

testing/web-platform/tests/url/urlsearchparams-constructor.html

@@ -148,7 +148,8 @@ test(function() {
 [
   { "input": {"+": "%C2"}, "output": [["+", "%C2"]], "name": "object with +" },
   { "input": {c: "x", a: "?"}, "output": [["c", "x"], ["a", "?"]], "name": "object with two keys" },
-  { "input": [["c", "x"], ["a", "?"]], "output": [["c", "x"], ["a", "?"]], "name": "array with two keys" }
+  { "input": [["c", "x"], ["a", "?"]], "output": [["c", "x"], ["a", "?"]], "name": "array with two keys" },
+  { "input": {"a\0b": "42", "c\uD83D": "23", "d\u1234": "foo"}, "output": [["a\0b", "42"], ["c\uFFFD", "23"], ["d\u1234", "foo"]], "name": "object with NULL, non-ASCII, and surrogate keys" }
 ].forEach((val) => {
     test(() => {
         let params = new URLSearchParams(val.input),