Revert of [proxies] Implement [[Enumerate]] and [[OwnPropertyKeys]]

test/mjsunit/harmony/proxies-enumerate.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-proxies
-
-var target = {
-  "target_one": 1
-};
-target.__proto__ = {
-  "target_two": 2
-};
-var handler = {
-  enumerate: function(target) {
-    function* keys() {
-      yield "foo";
-      yield "bar";
-    }
-    return keys();
-  }
-}
-
-var proxy = new Proxy(target, handler);
-
-function TestForIn(receiver, expected) {
-  var result = [];
-  for (var k in receiver) {
-    result.push(k);
-  }
-  assertEquals(expected, result);
-}
-
-TestForIn(proxy, ["foo", "bar"]);
-
-// Properly call traps on proxies on the prototype chain.
-var receiver = {
-  "receiver_one": 1
-};
-receiver.__proto__ = proxy;
-// TODO(jkummerow): Needs proper 'has' trap; implement that and enable this!
-// TestForIn(receiver, ["receiver_one", "foo", "bar"]);
-
-// Fall through to default behavior when trap is undefined.
-handler.enumerate = undefined;
-TestForIn(proxy, ["target_one", "target_two"]);
-delete handler.enumerate;
-TestForIn(proxy, ["target_one", "target_two"]);
-
-// Non-string keys must be filtered.
-function TestNonStringKey(key) {
-  handler.enumerate = function(target) {
-    function* keys() { yield key; }
-    return keys();
-  }
-  assertThrows("for (var k in proxy) {}", TypeError);
-}
-
-TestNonStringKey(1);
-TestNonStringKey(3.14);
-TestNonStringKey(Symbol("foo"));
-TestNonStringKey({bad: "value"});
-TestNonStringKey(null);
-TestNonStringKey(undefined);
-TestNonStringKey(true);