[api] Prototype WeakRef implementation

src/contexts.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_CONTEXTS_H_
 #define V8_CONTEXTS_H_
 
 #include "src/objects.h"
 
 namespace v8 {
@@ skipping 275 matching lines @@
     js_array_fast_double_elements_map_index)                                   \
   V(JS_ARRAY_FAST_HOLEY_DOUBLE_ELEMENTS_MAP_INDEX, Map,                        \
     js_array_fast_holey_double_elements_map_index)                             \
   V(JS_MAP_FUN_INDEX, JSFunction, js_map_fun)                                  \
   V(JS_MAP_MAP_INDEX, Map, js_map_map)                                         \
   V(JS_MODULE_NAMESPACE_MAP, Map, js_module_namespace_map)                     \
   V(JS_SET_FUN_INDEX, JSFunction, js_set_fun)                                  \
   V(JS_SET_MAP_INDEX, Map, js_set_map)                                         \
   V(JS_WEAK_MAP_FUN_INDEX, JSFunction, js_weak_map_fun)                        \
   V(JS_WEAK_SET_FUN_INDEX, JSFunction, js_weak_set_fun)                        \
+  V(JS_WEAK_REF_FUN_INDEX, JSFunction, js_weak_ref_fun)                        \
   V(MAP_CACHE_INDEX, Object, map_cache)                                        \
   V(MAP_ITERATOR_MAP_INDEX, Map, map_iterator_map)                             \
   V(MATH_RANDOM_INDEX_INDEX, Smi, math_random_index)                           \
   V(MATH_RANDOM_CACHE_INDEX, Object, math_random_cache)                        \
   V(MESSAGE_LISTENERS_INDEX, TemplateList, message_listeners)                  \
   V(NATIVES_UTILS_OBJECT_INDEX, Object, natives_utils_object)                  \
   V(NORMALIZED_MAP_CACHE_INDEX, Object, normalized_map_cache)                  \
   V(NUMBER_FUNCTION_INDEX, JSFunction, number_function)                        \
   V(OBJECT_FUNCTION_INDEX, JSFunction, object_function)                        \
   V(OBJECT_FUNCTION_PROTOTYPE_MAP_INDEX, Map, object_function_prototype_map)   \
@@ skipping 414 matching lines @@
   STATIC_ASSERT(kHeaderSize == Internals::kContextHeaderSize);
   STATIC_ASSERT(EMBEDDER_DATA_INDEX == Internals::kContextEmbedderDataIndex);
 };
 
 typedef Context::Field ContextField;
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CONTEXTS_H_