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

src/js/v8natives.js

Index: src/js/v8natives.js
diff --git a/src/js/v8natives.js b/src/js/v8natives.js
index 711a22fe64ca8e0a43aecf2fe8aaed46bc066d14..7cc426fb905ce58e604741e2576199d7817aeb77 100644
--- a/src/js/v8natives.js
+++ b/src/js/v8natives.js
@@ -27,7 +27,6 @@ var ObserveEndPerformSplice;
 var ObserveEnqueueSpliceRecord;
 var ProxyDelegateCallAndConstruct;
 var ProxyDerivedHasOwnTrap;
-var ProxyDerivedKeysTrap;
 var SameValue = utils.ImportNow("SameValue");
 var StringIndexOf;
 var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
@@ -47,7 +46,6 @@ utils.ImportFromExperimental(function(from) {
   FLAG_harmony_tostring = from.FLAG_harmony_tostring;
   ProxyDelegateCallAndConstruct = from.ProxyDelegateCallAndConstruct;
   ProxyDerivedHasOwnTrap = from.ProxyDerivedHasOwnTrap;
-  ProxyDerivedKeysTrap = from.ProxyDerivedKeysTrap;
 });
 
 // ----------------------------------------------------------------------------
@@ -274,11 +272,6 @@ function ObjectLookupSetter(name) {
 
 function ObjectKeys(obj) {
   obj = TO_OBJECT(obj);
-  if (%_IsJSProxy(obj)) {
-    var handler = %GetHandler(obj);
-    var names = CallTrap0(handler, "keys", ProxyDerivedKeysTrap);
-    return ToNameArray(names, "keys", false);
-  }
   return %OwnKeys(obj);
 }