[proxies] Implement [[Enumerate]] and [[OwnPropertyKeys]]

src/key-accumulator.cc

 // Copyright 2013 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.
 
 #include "src/key-accumulator.h"
 
 #include "src/elements.h"
 #include "src/factory.h"
 #include "src/objects-inl.h"
 
@@ skipping 199 matching lines @@
   // elements and properties, which breaks the normal assumption for the
   // KeyAccumulator.
   AddKeys(array_like, PROXY_MAGIC);
   // Invert the current length to indicate a present proxy, so we can ignore
   // element keys for this level. Otherwise we would not fully respect the order
   // given by the proxy.
   level_string_length_ = -level_string_length_;
 }
 
 
+void KeyAccumulator::AddKeysFromProxy(Handle<FixedArray> keys) {
+  // Proxies define a complete list of keys with no distinction of
+  // elements and properties, which breaks the normal assumption for the
+  // KeyAccumulator.
+  AddKeys(keys, PROXY_MAGIC);
+  // Invert the current length to indicate a present proxy, so we can ignore
+  // element keys for this level. Otherwise we would not fully respect the order
+  // given by the proxy.
+  level_string_length_ = -level_string_length_;
+}
+
+
 void KeyAccumulator::AddElementKeysFromInterceptor(
     Handle<JSObject> array_like) {
   AddKeys(array_like, CONVERT_TO_ARRAY_INDEX);
   // The interceptor might introduce duplicates for the current level, since
   // these keys get added after the objects's normal element keys.
   SortCurrentElementsListRemoveDuplicates();
 }
 
 
 void KeyAccumulator::SortCurrentElementsListRemoveDuplicates() {
@@ skipping 24 matching lines @@
     level_lengths_.push_back(level_symbol_length_);
   }
   elements_.push_back(new std::vector<uint32_t>());
   level_string_length_ = 0;
   level_symbol_length_ = 0;
 }
 
 
 }  // namespace internal
 }  // namespace v8