Replace AddProperty by AddNamedProperty to speed up the common case

src/math.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.
 
 "use strict";
 
 // This file relies on the fact that the following declarations have been made
 // in runtime.js:
 // var $Object = global.Object;
 
@@ skipping 242 matching lines @@
                          (dy - kCosXIntervalTable[index + 1]) * t1))
          * (1 - (phase & 2)) + 0;
 }
 
 // -------------------------------------------------------------------
 
 function SetUpMath() {
   %CheckIsBootstrapping();
 
   %SetPrototype($Math, $Object.prototype);
-  %AddProperty(global, "Math", $Math, DONT_ENUM);
+  %AddNamedProperty(global, "Math", $Math, DONT_ENUM);
   %FunctionSetInstanceClassName(MathConstructor, 'Math');
 
   // Set up math constants.
   InstallConstants($Math, $Array(
     // ECMA-262, section 15.8.1.1.
     "E", 2.7182818284590452354,
     // ECMA-262, section 15.8.1.2.
     "LN10", 2.302585092994046,
     // ECMA-262, section 15.8.1.3.
     "LN2", 0.6931471805599453,
@@ skipping 31 matching lines @@
 
   %SetInlineBuiltinFlag(MathCeil);
   %SetInlineBuiltinFlag(MathRandom);
   %SetInlineBuiltinFlag(MathSin);
   %SetInlineBuiltinFlag(MathCos);
   %SetInlineBuiltinFlag(MathTan);
   %SetInlineBuiltinFlag(TrigonometricInterpolation);
 }
 
 SetUpMath();