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

src/ia32/interface-descriptors-ia32.cc

Index: src/ia32/interface-descriptors-ia32.cc
diff --git a/src/ia32/interface-descriptors-ia32.cc b/src/ia32/interface-descriptors-ia32.cc
index 3a0d5268e07347f51146ba57ec9b3ffb88c1e5fc..f1af19b93d140bd0d4f093be3d0f9a25a0589e86 100644
--- a/src/ia32/interface-descriptors-ia32.cc
+++ b/src/ia32/interface-descriptors-ia32.cc
@@ -29,6 +29,9 @@ const Register StoreDescriptor::NameRegister() { return ecx; }
 const Register StoreDescriptor::ValueRegister() { return eax; }
 
 
+const Register ExtendStorageDescriptor::MapRegister() { return ebx; }
+
+
 const Register ElementTransitionAndStoreDescriptor::MapRegister() {
   return ebx;
 }