Reverty 1842 (see http://code.google.com/p/chromium/issues/detail?id=1717 )

src/array.js

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 993 matching lines @@
 }
 
 
 // -------------------------------------------------------------------
 
 function SetupArray() {
   // Setup non-enumerable constructor property on the Array.prototype
   // object.
   %SetProperty($Array.prototype, "constructor", $Array, DONT_ENUM);
 
-  // Setup non-enumerable functions of the Array.prototype object and set their
-  // names.  Use DONT_DELETE due to
-  // http://code.google.com/p/chromium/issues/detail?id=1717
-  InstallFunctions($Array.prototype, DONT_ENUM | DONT_DELETE, $Array(
+  // Setup non-enumerable functions of the Array.prototype object and
+  // set their names.
+  InstallFunctions($Array.prototype, DONT_ENUM, $Array(
     "toString", ArrayToString,
     "toLocaleString", ArrayToLocaleString,
     "join", ArrayJoin,
     "pop", ArrayPop,
     "push", ArrayPush,
     "concat", ArrayConcat,
     "reverse", ArrayReverse,
     "shift", ArrayShift,
     "unshift", ArrayUnshift,
     "slice", ArraySlice,
@@ skipping 21 matching lines @@
     ArrayIndexOf: 1,
     ArrayLastIndexOf: 1,
     ArrayPush: 1,
     ArrayReduce: 1,
     ArrayReduceRight: 1
   });
 }
 
 
 SetupArray();