Add NativeWeakMap to v8.h

src/runtime/runtime.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_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/zone.h"
@@ skipping 856 matching lines @@
 
   static void ArrayIdToTypeAndSize(int array_id, ExternalArrayType* type,
                                    ElementsKind* external_elements_kind,
                                    ElementsKind* fixed_elements_kind,
                                    size_t* element_size);
 
   // Used in runtime.cc and hydrogen's VisitArrayLiteral.
   MUST_USE_RESULT static MaybeHandle<Object> CreateArrayLiteralBoilerplate(
       Isolate* isolate, Handle<FixedArray> literals,
       Handle<FixedArray> elements);
+
+  static void WeakCollectionInitialize(
+      Isolate* isolate, Handle<JSWeakCollection> weak_collection);
+  static void WeakCollectionSet(Handle<JSWeakCollection> weak_collection,
+                                Handle<Object> key, Handle<Object> value);
+  static bool WeakCollectionDelete(Handle<JSWeakCollection> weak_collection,
+                                   Handle<Object> key);
 };
 
 
 std::ostream& operator<<(std::ostream&, Runtime::FunctionId);
 
 //---------------------------------------------------------------------------
 // Constants used by interface to runtime functions.
 
 class AllocateDoubleAlignFlag : public BitField<bool, 0, 1> {};
 class AllocateTargetSpace : public BitField<AllocationSpace, 1, 3> {};
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 STATIC_ASSERT(LANGUAGE_END == 2);
 class DeclareGlobalsLanguageMode : public BitField<LanguageMode, 2, 1> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_