V8 JavaScript shared memory prototype.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index 8d101631df9eddeb4bcdbfd7864087e99f97dee5..0e9512e1ed2d8522fc9be281eaace0f7240c31a9 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -5982,6 +5982,7 @@ v8::ArrayBuffer::Contents v8::ArrayBuffer::Externalize() {
   Contents contents;
   contents.data_ = obj->backing_store();
   contents.byte_length_ = byte_length;
+  contents.shared_ = obj->is_shared();
   return contents;
 }
 
@@ -6017,14 +6018,14 @@ Local<ArrayBuffer> v8::ArrayBuffer::New(Isolate* isolate, size_t byte_length) {
 
 
 Local<ArrayBuffer> v8::ArrayBuffer::New(Isolate* isolate, void* data,
-                                        size_t byte_length) {
+                                        size_t byte_length, bool shared) {
   i::Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
   EnsureInitializedForIsolate(i_isolate, "v8::ArrayBuffer::New(void*, size_t)");
   LOG_API(i_isolate, "v8::ArrayBuffer::New(void*, size_t)");
   ENTER_V8(i_isolate);
   i::Handle<i::JSArrayBuffer> obj =
       i_isolate->factory()->NewJSArrayBuffer();
-  i::Runtime::SetupArrayBuffer(i_isolate, obj, true, data, byte_length);
+  i::Runtime::SetupArrayBuffer(i_isolate, obj, true, data, byte_length, shared);
   return Utils::ToLocal(obj);
 }