Avoid converting key to string for deleting of elements

src/runtime.js

 // Copyright 2006-2008 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 files contains runtime support implemented in JavaScript.
 
 // CAUTION: Some of the functions specified in this file are called
 // directly from compiled code. These are the functions with names in
 // ALL CAPS. The compiled code passes the first argument in 'this'.
 
@@ skipping 491 matching lines @@
 }
 
 
 /* -----------------------------
    - - -   H e l p e r s   - - -
    -----------------------------
 */
 
 // ECMA-262, section 11.4.1, page 46.
 DELETE = function DELETE(key, language_mode) {
-  return %DeleteProperty(%$toObject(this), %$toName(key), language_mode);
+  return %DeleteProperty(%$toObject(this), key, language_mode);
 }
 
 
 // ECMA-262, section 11.8.7, page 54.
 IN = function IN(x) {
   if (!IS_SPEC_OBJECT(x)) {
     throw %MakeTypeError(kInvalidInOperatorUse, this, x);
   }
   if (%_IsNonNegativeSmi(this)) {
     if (IS_ARRAY(x) && %_HasFastPackedElements(x)) {
@@ skipping 518 matching lines @@
 $toLength = ToLength;
 $toName = ToName;
 $toNumber = ToNumber;
 $toObject = ToObject;
 $toPositiveInteger = ToPositiveInteger;
 $toPrimitive = ToPrimitive;
 $toString = ToString;
 $toUint32 = ToUint32;
 
 })