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

src/builtins/builtins-function.cc

 // Copyright 2016 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/builtins/builtins.h"
 #include "src/builtins/builtins-utils.h"
 
 #include "src/compiler.h"
 #include "src/string-builder.h"
 
@@ skipping 180 matching lines @@
 
   LookupIterator length_lookup(target, isolate->factory()->length_string(),
                                target, LookupIterator::OWN);
   // Setup the "length" property based on the "length" of the {target}.
   // If the targets length is the default JSFunction accessor, we can keep the
   // accessor that's installed by default on the JSBoundFunction. It lazily
   // computes the value from the underlying internal length.
   if (!target->IsJSFunction() ||
       length_lookup.state() != LookupIterator::ACCESSOR ||
       !length_lookup.GetAccessors()->IsAccessorInfo()) {
-    Handle<Object> length(Smi::FromInt(0), isolate);
+    Handle<Object> length(Smi::kZero, isolate);
     Maybe<PropertyAttributes> attributes =
         JSReceiver::GetPropertyAttributes(&length_lookup);
     if (!attributes.IsJust()) return isolate->heap()->exception();
     if (attributes.FromJust() != ABSENT) {
       Handle<Object> target_length;
       ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, target_length,
                                          Object::GetProperty(&length_lookup));
       if (target_length->IsNumber()) {
         length = isolate->factory()->NewNumber(std::max(
             0.0, DoubleToInteger(target_length->Number()) - argv.length()));
@@ skipping 76 matching lines @@
 
   Node* f = assembler->Parameter(0);
   Node* v = assembler->Parameter(1);
   Node* context = assembler->Parameter(4);
   Node* result = assembler->OrdinaryHasInstance(context, f, v);
   assembler->Return(result);
 }
 
 }  // namespace internal
 }  // namespace v8