Revert of Always optimize for adding properties to native objects.

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.
 
 // This file relies on the fact that the following declarations have been made
 // in runtime.js:
 // var $Object = global.Object;
 // var $Boolean = global.Boolean;
 // var $Number = global.Number;
 // var $Function = global.Function;
 // var $Array = global.Array;
 
 var $isNaN = GlobalIsNaN;
 var $isFinite = GlobalIsFinite;
 
 // ----------------------------------------------------------------------------
 
 // Helper function used to install functions on objects.
 function InstallFunctions(object, attributes, functions) {
-  %OptimizeObjectForAddingMultipleProperties(object, functions.length >> 1);
+  if (functions.length >= 8) {
+    %OptimizeObjectForAddingMultipleProperties(object, functions.length >> 1);
+  }
   for (var i = 0; i < functions.length; i += 2) {
     var key = functions[i];
     var f = functions[i + 1];
     %FunctionSetName(f, key);
     %FunctionRemovePrototype(f);
     %AddNamedProperty(object, key, f, attributes);
     %SetNativeFlag(f);
   }
   %ToFastProperties(object);
 }
@@ skipping 29 matching lines @@
   %FunctionRemovePrototype(getter);
   %FunctionRemovePrototype(setter);
   %DefineAccessorPropertyUnchecked(object, name, getter, setter, DONT_ENUM);
   %SetNativeFlag(getter);
   %SetNativeFlag(setter);
 }
 
 
 // Helper function for installing constant properties on objects.
 function InstallConstants(object, constants) {
-  %OptimizeObjectForAddingMultipleProperties(object, constants.length >> 1);
+  if (constants.length >= 4) {
+    %OptimizeObjectForAddingMultipleProperties(object, constants.length >> 1);
+  }
   var attributes = DONT_ENUM | DONT_DELETE | READ_ONLY;
   for (var i = 0; i < constants.length; i += 2) {
     var name = constants[i];
     var k = constants[i + 1];
     %AddNamedProperty(object, name, k, attributes);
   }
   %ToFastProperties(object);
 }
 
 
@@ skipping 1825 matching lines @@
   }
   if (!IS_SPEC_FUNCTION(method)) {
     throw MakeTypeError(kNotIterable, obj);
   }
   var iterator = %_CallFunction(obj, method);
   if (!IS_SPEC_OBJECT(iterator)) {
     throw MakeTypeError(kNotAnIterator, iterator);
   }
   return iterator;
 }