[es6] Implement for-of iterator finalization

test/mjsunit/harmony/destructuring.js

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Flags: --harmony-destructuring-bind
 // Flags: --harmony-default-parameters
 
 (function TestObjectLiteralPattern() {
   var { x : x, y : y, get, set } = { x : 1, y : 2, get: 3, set: 4 };
   assertEquals(1, x);
@@ skipping 1043 matching lines @@
   function f6(x, ...a) { x = 2; return arguments[0] }
   assertEquals(6, f6(6, {}));
   function f7({a: x}) { x = 2; return arguments[0].a }
   assertEquals(5, f7({a: 5}));
   function f8(x, ...a) { a = []; return arguments[1] }
   assertEquals(6, f8(5, 6));
 }());
 
 
 (function TestForInOfTDZ() {
-  assertThrows("'use strict'; let x = {}; for (let [x, y] of {x});", ReferenceError);
-  assertThrows("'use strict'; let x = {}; for (let [y, x] of {x});", ReferenceError);
+  assertThrows("'use strict'; let x = {}; for (let [x, y] of [x]);", ReferenceError);
+  assertThrows("'use strict'; let x = {}; for (let [y, x] of [x]);", ReferenceError);
   assertThrows("'use strict'; let x = {}; for (let [x, y] in {x});", ReferenceError);
   assertThrows("'use strict'; let x = {}; for (let [y, x] in {x});", ReferenceError);
 }());
 
 
 (function TestFunctionLength() {
    assertEquals(1, (function({}) {}).length);
    assertEquals(1, (function([]) {}).length);
    assertEquals(1, (function({x}) {}).length);
    assertEquals(1, (function({}, ...a) {}).length);
@@ skipping 49 matching lines @@
     throw [1, 2, 3];
   } catch ([foo, ...bar]) {
     assertEquals(1, foo);
     assertEquals([2, 3], bar);
   }
 
   assertEquals("hello", foo);
   assertEquals("world", bar);
   assertEquals(42, baz);
 })();