WIP SharedArrayBuffer implementation

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index 72991d9bf0ca7ef405c170a6f19029a5a2f3305f..6d112a52301e86f3113a2475ec6dc231aa88ab72 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -444,16 +444,18 @@ class Factory final {
 
   Handle<JSGeneratorObject> NewJSGeneratorObject(Handle<JSFunction> function);
 
-  Handle<JSArrayBuffer> NewJSArrayBuffer();
+  Handle<JSArrayBuffer> NewJSArrayBuffer(SharedFlag is_shared = NOT_SHARED);
 
-  Handle<JSTypedArray> NewJSTypedArray(ExternalArrayType type);
+  Handle<JSTypedArray> NewJSTypedArray(ExternalArrayType type,
+                                       SharedFlag is_shared = NOT_SHARED);
 
   Handle<JSTypedArray> NewJSTypedArray(ElementsKind elements_kind);
 
   // Creates a new JSTypedArray with the specified buffer.
   Handle<JSTypedArray> NewJSTypedArray(ExternalArrayType type,
                                        Handle<JSArrayBuffer> buffer,
-                                       size_t byte_offset, size_t length);
+                                       size_t byte_offset, size_t length,
+                                       SharedFlag is_shared = NOT_SHARED);
 
   // Creates a new on-heap JSTypedArray.
   Handle<JSTypedArray> NewJSTypedArray(ElementsKind elements_kind,