Add Smi::Zero and replace all Smi::FromInt(0) calls

src/keys.cc

 // Copyright 2013 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.
 
 #include "src/keys.h"
 
 #include "src/api-arguments.h"
 #include "src/elements.h"
 #include "src/factory.h"
 #include "src/identity-map.h"
@@ skipping 762 matching lines @@
     Maybe<bool> found = JSReceiver::GetOwnPropertyDescriptor(
         isolate_, target, handle(target_keys->get(i), isolate_), &desc);
     MAYBE_RETURN(found, Nothing<bool>());
     // 14b. If desc is not undefined and desc.[[Configurable]] is false, then
     if (found.FromJust() && !desc.configurable()) {
       // 14b i. Append key as an element of targetNonconfigurableKeys.
       target_nonconfigurable_keys->set(nonconfigurable_keys_length,
                                        target_keys->get(i));
       nonconfigurable_keys_length++;
       // The key was moved, null it out in the original list.
-      target_keys->set(i, Smi::FromInt(0));
+      target_keys->set(i, Smi::kZero);
     } else {
       // 14c. Else,
       // 14c i. Append key as an element of targetConfigurableKeys.
       // (No-op, just keep it in |target_keys|.)
     }
   }
   // 15. If extensibleTarget is true and targetNonconfigurableKeys is empty,
   //     then:
   if (extensible_target && nonconfigurable_keys_length == 0) {
     // 15a. Return trapResult.
@@ skipping 68 matching lines @@
       isolate_, keys,
       KeyAccumulator::GetKeys(target, KeyCollectionMode::kOwnOnly, filter_,
                               GetKeysConversion::kConvertToString, is_for_in_),
       Nothing<bool>());
   Maybe<bool> result = AddKeysFromJSProxy(proxy, keys);
   return result;
 }
 
 }  // namespace internal
 }  // namespace v8