Clean up hash creation code to use Handle<Smi> where possible

src/objects-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 6302 matching lines @@
 bool JSGlobalObject::IsDetached() {
   return JSGlobalProxy::cast(global_receiver())->IsDetachedFrom(this);
 }
 
 
 bool JSGlobalProxy::IsDetachedFrom(GlobalObject* global) {
   return GetPrototype() != global;
 }
 
 
-Handle<Object> JSReceiver::GetOrCreateIdentityHash(Handle<JSReceiver> object) {
+Handle<Smi> JSReceiver::GetOrCreateIdentityHash(Handle<JSReceiver> object) {
   return object->IsJSProxy()
       ? JSProxy::GetOrCreateIdentityHash(Handle<JSProxy>::cast(object))
       : JSObject::GetOrCreateIdentityHash(Handle<JSObject>::cast(object));
 }
 
 
 Object* JSReceiver::GetIdentityHash() {
   return IsJSProxy()
       ? JSProxy::cast(this)->GetIdentityHash()
       : JSObject::cast(this)->GetIdentityHash();
@@ skipping 522 matching lines @@
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_