Reland of [keys] Simplify KeyAccumulator

test/mjsunit/es6/reflect.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.
 
 // TODO(neis): Test with proxies.
 
 
 
 ////////////////////////////////////////////////////////////////////////////////
 // (Auxiliaries)
@@ skipping 523 matching lines @@
 (function testReflectOwnKeysOnObject(){
   assertEquals(["z", "y", "x"], Reflect.ownKeys({z: 3, y: 2, x: 1}));
   assertEquals(["length"], Reflect.ownKeys([]));
 
   var s1 = Symbol("foo");
   var s2 = Symbol("bar");
   var obj = { [s1]: 0, "bla": 0, 42: 0, "0": 0,
       [s2]: 0, "-1": 0, "88": 0, "aaa": 0 };
   assertEquals(["0", "42", "88", "bla", "-1", "aaa", s1, s2],
       Reflect.ownKeys(obj));
+  // Force dict-mode elements.
+  delete obj[0];
+  assertEquals(["42", "88", "bla", "-1", "aaa", s1, s2],
+      Reflect.ownKeys(obj));
+  // Force dict-mode properties.
+  delete obj["bla"];
+  assertEquals(["42", "88", "-1", "aaa", s1, s2], Reflect.ownKeys(obj));
 })();
 
 
 // See reflect-own-keys.js for further tests.
 
 
 
 ////////////////////////////////////////////////////////////////////////////////
 // Reflect.preventExtensions
 
 
 (function testReflectPreventExtensionsArity() {
   assertEquals(1, Reflect.preventExtensions.length);
 })();
 
 
 (function testReflectPreventExtensionsOnNonObject() {
   assertThrows(function() { Reflect.preventExtensions(); }, TypeError);
   assertThrows(function() { Reflect.preventExtensions(42); }, TypeError);
   assertThrows(function() { Reflect.preventExtensions(null); }, TypeError);
 })();
 
 
 // See reflect-prevent-extensions.js for further tests.
 
 // TODO(neis): Need proxies to test the situation where
 // [[preventExtensions]] returns false.