Add Object.isFrozen test

test/built-ins/Object/isFrozen/proxy-no-ownkeys-returned-keys-order.js

@@ -0,0 +1,52 @@
+// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-object.isfrozen
+description: >
+  If Proxy "ownKeys" trap is missing, keys are sorted by type in ascending
+  chronological order.
+info: |
+  TestIntegrityLevel ( O, level )
+
+  [...]
+  6. Let keys be ? O.[[OwnPropertyKeys]]().
+  7. For each element k of keys, do
+    a. Let currentDesc be ? O.[[GetOwnProperty]](k).
+
+  [[OwnPropertyKeys]] ( )
+
+  [...]
+  6. If trap is undefined, then
+    a. Return ? target.[[OwnPropertyKeys]]().
+
+  OrdinaryOwnPropertyKeys ( O )
+
+  [...]
+  3. For each own property key P of O such that Type(P) is String and P is
+  not an array index, in ascending chronological order of property creation, do
+    a. Add P as the last element of keys.
+  4. For each own property key P of O such that Type(P) is Symbol,
+  in ascending chronological order of property creation, do
+    a. Add P as the last element of keys.
+  5. Return keys.
+features: [Proxy, Symbol, Reflect]
+includes: [compareArray.js]
+---*/
+
+var target = {};
+var sym = Symbol();
+target[sym] = 1;
+target.foo = 2;
+target[0] = 3;
+Object.freeze(target);
+
+var getOwnKeys = [];
+var proxy = new Proxy(target, {
+  getOwnPropertyDescriptor: function(target, key) {
+    getOwnKeys.push(key);
+    return Reflect.getOwnPropertyDescriptor(target, key);
+  },
+});
+
+Object.isFrozen(proxy);
+assert.compareArray(getOwnKeys, ["0", "foo", sym]);