Avoid duplicate lookups when Get+Creating identity hashes

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 3d453c2679b7a933ddfdd5694a5eefa9a86012b1..5bdfb0df7d8581b46c33a011947d9069809e7a67 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -1049,15 +1049,24 @@ bool Object::HasSpecificClassOf(String* name) {
 MaybeHandle<Object> Object::GetProperty(Handle<Object> object,
                                         Handle<Name> name) {
   LookupIterator it(object, name);
+  if (!it.IsFound()) return it.factory()->undefined_value();
   return GetProperty(&it);
 }
 
 MaybeHandle<Object> Object::GetElement(Isolate* isolate, Handle<Object> object,
                                        uint32_t index) {
   LookupIterator it(isolate, object, index);
+  if (!it.IsFound()) return it.factory()->undefined_value();
   return GetProperty(&it);
 }
 
+Handle<Object> JSReceiver::GetDataProperty(Handle<JSReceiver> object,
+                                           Handle<Name> name) {
+  LookupIterator it(object, name,
+                    LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR);
+  if (!it.IsFound()) return it.factory()->undefined_value();
+  return GetDataProperty(&it);
+}
 
 MaybeHandle<Object> Object::SetElement(Isolate* isolate, Handle<Object> object,
                                        uint32_t index, Handle<Object> value,