[runtime] Do not use the enum-cache for non-prototype objects.

src/key-accumulator.h

 // Copyright 2012 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_KEY_ACCUMULATOR_H_
 #define V8_KEY_ACCUMULATOR_H_
 
+#include <algorithm>

[Jakob Kummerow, 2016/01/19 15:32:53]

nit: I guess this can be moved to the .cc file?

+#include <set>
+
 #include "src/isolate.h"
 #include "src/objects.h"
 
 namespace v8 {
 namespace internal {
 
 enum AddKeyConversion { DO_NOT_CONVERT, CONVERT_TO_ARRAY_INDEX, PROXY_MAGIC };
 
 // This is a helper class for JSReceiver::GetKeys which collects and sorts keys.
 // GetKeys needs to sort keys per prototype level, first showing the integer
@@ skipping 20 matching lines @@
   bool AddKey(uint32_t key);
   bool AddKey(Object* key, AddKeyConversion convert = DO_NOT_CONVERT);
   bool AddKey(Handle<Object> key, AddKeyConversion convert = DO_NOT_CONVERT);
   void AddKeys(Handle<FixedArray> array,
                AddKeyConversion convert = DO_NOT_CONVERT);
   void AddKeys(Handle<JSObject> array,
                AddKeyConversion convert = DO_NOT_CONVERT);
   void AddKeysFromProxy(Handle<JSObject> array);
   Maybe<bool> AddKeysFromProxy(Handle<JSProxy> proxy, Handle<FixedArray> keys);
   void AddElementKeysFromInterceptor(Handle<JSObject> array);
+  void HideKey(uint32_t key);
+  void HideKey(Object* key);
+  void HideKey(Handle<Object> key);
   // Jump to the next level, pushing the current |levelLength_| to
   // |levelLengths_| and adding a new list to |elements_|.
   void NextPrototype();
   // Sort the integer indices in the last list in |elements_|
   void SortCurrentElementsList();
   Handle<FixedArray> GetKeys(GetKeysConversion convert = KEEP_NUMBERS);
   int length() { return length_; }
   Isolate* isolate() { return isolate_; }
 
  private:
   bool AddIntegerKey(uint32_t key);
   bool AddStringKey(Handle<Object> key, AddKeyConversion convert);
   bool AddSymbolKey(Handle<Object> array);
   void SortCurrentElementsListRemoveDuplicates();
+  bool IsKeyHidden(Handle<Object> key);
+  bool IsKeyHidden(uint32_t key);
 
   Isolate* isolate_;
   PropertyFilter filter_;
   // |elements_| contains the sorted element keys (indices) per level.
   std::vector<std::vector<uint32_t>*> elements_;
   // |protoLengths_| contains the total number of keys (elements + properties)
   // per level. Negative values mark counts for a level with keys from a proxy.
   std::vector<int> level_lengths_;
   // |string_properties_| contains the unique String property keys for all
   // levels in insertion order per level.
   Handle<OrderedHashSet> string_properties_;
   // |symbol_properties_| contains the unique Symbol property keys for all
   // levels in insertion order per level.
   Handle<OrderedHashSet> symbol_properties_;
+  // |hidden_keys_| keeps track of the non-enumerable property keys to prevent
+  // them from being added to the accumulator if they reappear higher up in the
+  // prototype-chain.
+  Handle<OrderedHashSet> hidden_keys_;
+  std::set<uint32_t> hidden_element_keys_;
   // |length_| keeps track of the total number of all element and property keys.
   int length_ = 0;
   // |levelLength_| keeps track of the number of String keys in the current
   // level.
   int level_string_length_ = 0;
   // |levelSymbolLength_| keeps track of the number of Symbol keys in the
   // current level.
   int level_symbol_length_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(KeyAccumulator);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 
 #endif  // V8_KEY_ACCUMULATOR_H_