Revert "Inline instance object hash code into object header on 64 bit."

runtime/lib/object.cc

Index: runtime/lib/object.cc
diff --git a/runtime/lib/object.cc b/runtime/lib/object.cc
index f0739adc3acdfdebdf0a6430ee4fdc9d0bbde187..b7dcea3a2088351939f96dbb7ef5d1c8b07932bf 100644
--- a/runtime/lib/object.cc
+++ b/runtime/lib/object.cc
@@ -42,25 +42,17 @@ DEFINE_NATIVE_ENTRY(Object_getHash, 1) {
   // Please note that no handle is created for the argument.
   // This is safe since the argument is only used in a tail call.
   // The performance benefit is more than 5% when using hashCode.
-#if defined(HASH_IN_OBJECT_HEADER)
-  return Smi::New(Object::GetCachedHash(arguments->NativeArgAt(0)));
-#else
   Heap* heap = isolate->heap();
   ASSERT(arguments->NativeArgAt(0)->IsDartInstance());
   return Smi::New(heap->GetHash(arguments->NativeArgAt(0)));
-#endif
 }
 
 
 DEFINE_NATIVE_ENTRY(Object_setHash, 2) {
-  GET_NON_NULL_NATIVE_ARGUMENT(Smi, hash, arguments->NativeArgAt(1));
-#if defined(HASH_IN_OBJECT_HEADER)
-  Object::SetCachedHash(arguments->NativeArgAt(0), hash.Value());
-#else
   const Instance& instance = Instance::CheckedHandle(arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(Smi, hash, arguments->NativeArgAt(1));
   Heap* heap = isolate->heap();
   heap->SetHash(instance.raw(), hash.Value());
-#endif
   return Object::null();
 }