Fix corner case in iterator finalization for array destructuring.

test/mjsunit/harmony/iterator-close.js

 // Copyright 2016 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-iterator-close
 
 
 function* g() { yield 42; return 88 };
 
 
@@ skipping 992 matching lines @@
   assertThrowsEquals(() => {
     [x] = g();
   }, 666);
 
   assertThrowsEquals(() => {
     (([x]) => x)(g());
   }, 666);
 }
 
 
+// Value throws.
+{
+  g.prototype.next = () => ({get value() {throw 666}});
+  g.prototype.return = () => { assertUnreachable() };
+
+
+  assertThrowsEquals(() => {
+    for (var x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    for (let x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    for (const x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    for (x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    var [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    let [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    const [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    (([x]) => x)(g());
+  }, 666);
+}
+
+
+// Done throws.
+{
+  g.prototype.next = () => ({get done() {throw 666}});
+  g.prototype.return = () => { assertUnreachable() };
+
+
+  assertThrowsEquals(() => {
+    for (var x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    for (let x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    for (const x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    for (x of g()) {}
+  }, 666);
+
+  assertThrowsEquals(() => {
+    var [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    let [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    const [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    [x] = g();
+  }, 666);
+
+  assertThrowsEquals(() => {
+    (([x]) => x)(g());
+  }, 666);
+}
+
+
 // Nested loops.
 {
   function* g1() { yield 1; yield 2; throw 3; }
   function* g2() { yield -1; yield -2; throw -3; }
 
   assertDoesNotThrow(() => {
     for (let x of g1()) {
       for (let y of g2()) {
         if (y == -2) break;
       }
@@ skipping 120 matching lines @@
     for (let x of g1()) {
       try {
         for (let y of g2()) {
         }
       } catch (_) {}
       if (x == 2) break;
     }
   }, 5);
   assertEquals([1], log);
 }