[proxies] Implement Symbol/DONT_ENUM filtering for GetKeys()

src/js/proxy.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.
 
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
@@ skipping 116 matching lines @@
     writable: true,
     enumerable: true,
     configurable: true});
   return true;
 }
 
 function DerivedHasOwnTrap(name) {
   return !!this.getOwnPropertyDescriptor(name)
 }
 
-function DerivedKeysTrap() {
-  var names = this.getOwnPropertyNames()
-  var enumerableNames = []
-  for (var i = 0, count = 0; i < names.length; ++i) {
-    var name = names[i]
-    if (IS_SYMBOL(name)) continue
-    var desc = this.getOwnPropertyDescriptor(TO_STRING(name))
-    if (!IS_UNDEFINED(desc) && desc.enumerable) {
-      enumerableNames[count++] = names[i]
-    }
-  }
-  return enumerableNames
-}
 
 // Implements part of ES6 9.5.11 Proxy.[[Enumerate]]:
 // Call the trap, which should return an iterator, exhaust the iterator,
 // and return an array containing the values.
 function ProxyEnumerate(trap, handler, target) {
   // 7. Let trapResult be ? Call(trap, handler, «target»).
   var trap_result = %_Call(trap, handler, target);
   // 8. If Type(trapResult) is not Object, throw a TypeError exception.
   if (!IS_SPEC_OBJECT(trap_result)) {
     throw MakeTypeError(kProxyHandlerReturned, handler, "non-Object",
@@ skipping 21 matching lines @@
 utils.InstallFunctions(GlobalProxy, DONT_ENUM, [
   "createFunction", ProxyCreateFunction
 ]);
 
 // -------------------------------------------------------------------
 // Exports
 
 utils.Export(function(to) {
   to.ProxyDelegateCallAndConstruct = DelegateCallAndConstruct;
   to.ProxyDerivedHasOwnTrap = DerivedHasOwnTrap;
-  to.ProxyDerivedKeysTrap = DerivedKeysTrap;
 });
 
 %InstallToContext([
   "derived_get_trap", DerivedGetTrap,
   "derived_set_trap", DerivedSetTrap,
   "proxy_enumerate", ProxyEnumerate,
 ]);
 
 })