[proxies] allow duplicate keys for [[OwnPropertyKeys]] trap.

src/objects.h

 // 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.
 
 #ifndef V8_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 1767 matching lines @@
 
 // Indicator for one component of an AccessorPair.
 enum AccessorComponent {
   ACCESSOR_GETTER,
   ACCESSOR_SETTER
 };
 
 
 enum GetKeysConversion { KEEP_NUMBERS, CONVERT_TO_STRING };
 
+enum KeyCollectionType { OWN_ONLY, INCLUDE_PROTOS };
 
 // JSReceiver includes types on which properties can be defined, i.e.,
 // JSObject and JSProxy.
 class JSReceiver: public HeapObject {
  public:
   // [properties]: Backing storage for properties.
   // properties is a FixedArray in the fast case and a Dictionary in the
   // slow case.
   DECL_ACCESSORS(properties, FixedArray)  // Get and set fast properties.
   inline void initialize_properties();
@@ skipping 141 matching lines @@
 
   // Retrieves a permanent object identity hash code. The undefined value might
   // be returned in case no hash was created yet.
   inline Object* GetIdentityHash();
 
   // Retrieves a permanent object identity hash code. May create and store a
   // hash code if needed and none exists.
   inline static Handle<Smi> GetOrCreateIdentityHash(
       Handle<JSReceiver> object);
 
-  enum KeyCollectionType { OWN_ONLY, INCLUDE_PROTOS };
-
   // ES6 [[OwnPropertyKeys]] (modulo return type)
   MUST_USE_RESULT static MaybeHandle<FixedArray> OwnPropertyKeys(
       Handle<JSReceiver> object) {
-    return GetKeys(object, JSReceiver::OWN_ONLY, ALL_PROPERTIES,
-                   CONVERT_TO_STRING);
+    return GetKeys(object, OWN_ONLY, ALL_PROPERTIES, CONVERT_TO_STRING);
   }
 
   // Computes the enumerable keys for a JSObject. Used for implementing
   // "for (n in object) { }".
   MUST_USE_RESULT static MaybeHandle<FixedArray> GetKeys(
       Handle<JSReceiver> object, KeyCollectionType type, PropertyFilter filter,
       GetKeysConversion keys_conversion = KEEP_NUMBERS);
 
   // Layout description.
   static const int kPropertiesOffset = HeapObject::kHeaderSize;
@@ skipping 8839 matching lines @@
     }
     return value;
   }
 };
 
 
 }  // NOLINT, false-positive due to second-order macros.
 }  // NOLINT, false-positive due to second-order macros.
 
 #endif  // V8_OBJECTS_H_