VM: Reland Inline instance object hash code into object header on 64bit.

runtime/vm/clustered_snapshot.cc

Index: runtime/vm/clustered_snapshot.cc
diff --git a/runtime/vm/clustered_snapshot.cc b/runtime/vm/clustered_snapshot.cc
index 56f766f12be9fac832267c510f8fd1b84074f7a3..a5346975c0b9972b38066db3c30421f50ddb3e45 100644
--- a/runtime/vm/clustered_snapshot.cc
+++ b/runtime/vm/clustered_snapshot.cc
@@ -40,12 +40,15 @@ void Deserializer::InitializeHeader(RawObject* raw,
                                     bool is_vm_isolate,
                                     bool is_canonical) {
   ASSERT(Utils::IsAligned(size, kObjectAlignment));
-  uword tags = 0;
+  uint32_t tags = 0;
   tags = RawObject::ClassIdTag::update(class_id, tags);
   tags = RawObject::SizeTag::update(size, tags);
   tags = RawObject::VMHeapObjectTag::update(is_vm_isolate, tags);
   tags = RawObject::CanonicalObjectTag::update(is_canonical, tags);
   raw->ptr()->tags_ = tags;
+#if defined(HASH_IN_OBJECT_HEADER)
+  raw->ptr()->hash_ = 0;
+#endif
 }