ExtendStorageStub added, it is aimed for extending objects backing store when it runs out of space.

src/arm64/interface-descriptors-arm64.cc

Index: src/arm64/interface-descriptors-arm64.cc
diff --git a/src/arm64/interface-descriptors-arm64.cc b/src/arm64/interface-descriptors-arm64.cc
index 690c8c28eeb83f16fede90bcae48612b2fa97214..e77f2a467280f713d6d853718afcb835c64bfbb1 100644
--- a/src/arm64/interface-descriptors-arm64.cc
+++ b/src/arm64/interface-descriptors-arm64.cc
@@ -27,6 +27,9 @@ const Register VectorLoadICDescriptor::VectorRegister() { return x3; }
 const Register StoreDescriptor::ReceiverRegister() { return x1; }
 const Register StoreDescriptor::NameRegister() { return x2; }
 const Register StoreDescriptor::ValueRegister() { return x0; }
+const Register ExtendStorageDescriptor::MapRegister() {
+  return StoreDescriptor::NameRegister();
+}
 
 
 const Register ElementTransitionAndStoreDescriptor::MapRegister() { return x3; }