In-heap small typed arrays

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index f61f190291ecc3365f09e94b60d350a44601adb3..2530ac660e1d7d2e76c6c3f373d816364624b12f 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -6018,8 +6018,15 @@ Local<ArrayBuffer> v8::ArrayBuffer::New(Isolate* isolate, void* data,
 
 Local<ArrayBuffer> v8::ArrayBufferView::Buffer() {
   i::Handle<i::JSArrayBufferView> obj = Utils::OpenHandle(this);
-  ASSERT(obj->buffer()->IsJSArrayBuffer());
-  i::Handle<i::JSArrayBuffer> buffer(i::JSArrayBuffer::cast(obj->buffer()));
+  i::Handle<i::JSArrayBuffer> buffer;
+  if (obj->IsJSDataView()) {
+    i::Handle<i::JSDataView> data_view(i::JSDataView::cast(*obj));
+    ASSERT(data_view->buffer()->IsJSArrayBuffer());
+    buffer = i::handle(i::JSArrayBuffer::cast(data_view->buffer()));
+  } else {
+    ASSERT(obj->IsJSTypedArray());
+    buffer = i::JSTypedArray::cast(*obj)->GetBuffer();
+  }
   return Utils::ToLocal(buffer);
 }
 
@@ -6090,7 +6097,9 @@ i::Handle<i::JSTypedArray> NewTypedArray(
       isolate->factory()->NewExternalArray(
           static_cast<int>(length), array_type,
           static_cast<uint8_t*>(buffer->backing_store()) + byte_offset);
-  obj->set_elements(*elements);
+  i::Handle<i::Map> map =
+      i::JSObject::GetElementsTransitionMap(obj, elements_kind);
+  obj->set_map_and_elements(*map, *elements);
   return obj;
 }