Store offset between fixed typed array base and data start in object

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index 04a580019e9cf5f1b97a9e52aed99abc91c74748..073bffcf897ea39ee19f19651f7382920f1def04 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -4027,6 +4027,9 @@ AllocationResult Heap::AllocateFixedTypedArray(int length,
   object->set_map(MapForFixedTypedArray(array_type));
   FixedTypedArrayBase* elements = FixedTypedArrayBase::cast(object);
   elements->set_base_pointer(elements, SKIP_WRITE_BARRIER);
+  elements->set_external_pointer(
+      ExternalReference::fixed_typed_array_base_data_offset().address(),
+      SKIP_WRITE_BARRIER);
   elements->set_length(length);
   if (initialize) memset(elements->DataPtr(), 0, elements->DataSize());
   return elements;