Remove unnecessary checks and runtime calls from ToLength

src/v8natives.js

 // 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.
 
 (function(global, utils) {
 
 %CheckIsBootstrapping();
 
 // ----------------------------------------------------------------------------
 // Imports
@@ skipping 1523 matching lines @@
 function NumberIsNaN(number) {
   return IS_NUMBER(number) && NUMBER_IS_NAN(number);
 }
 
 
 // Harmony isSafeInteger
 function NumberIsSafeInteger(number) {
   if (NumberIsFinite(number)) {
     var integral = TO_INTEGER(number);
     if (integral == number) {
-      return MathAbs(integral) <= GlobalNumber.MAX_SAFE_INTEGER;
+      return MathAbs(integral) <= kMaxSafeInteger;
     }
   }
   return false;
 }
 
 
 // ----------------------------------------------------------------------------
 
 %SetCode(GlobalNumber, NumberConstructor);
 %FunctionSetPrototype(GlobalNumber, new GlobalNumber(0));
@@ skipping 255 matching lines @@
 });
 
 utils.ExportToRuntime(function(to) {
   to["global_eval_fun"] = GlobalEval;
   to["object_define_own_property"] = DefineOwnPropertyFromAPI;
   to["object_get_own_property_descriptor"] = ObjectGetOwnPropertyDescriptor;
   to["to_complete_property_descriptor"] = ToCompletePropertyDescriptor;
 });
 
 })