The constructor properties on the prototypes of error objects should...

src/messages.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 621 matching lines @@
   // within the runtime system to avoid strange side
   // effects when overwriting the error functions from
   // user code.
   var name = f.name;
   %SetProperty(global, name, f, DONT_ENUM);
   this['$' + name] = f;
   // Configure the error function.
   // prototype of 'Error' must be as default: new Object().
   if (name != 'Error') %FunctionSetPrototype(f, new $Error());
   %FunctionSetInstanceClassName(f, 'Error');
+  %SetProperty(f.prototype, 'constructor', f, DONT_ENUM);
   f.prototype.name = name;
-  f.prototype.constructor = f;
   %SetCode(f, function(m) {
     if (%IsConstructCall()) {
       if (!IS_UNDEFINED(m)) this.message = ToString(m);
     } else {
       return new f(m);
     }
   });
 }
 
 $Math.__proto__ = global.Object.prototype;
@@ skipping 15 matching lines @@
     return this.name + ": " + FormatMessage({ type: type, args: this.arguments });
   }
   var message = this.message;
   return this.name + (message ? (": " + message) : "");
 }, DONT_ENUM);
 
 
 // Boilerplate for exceptions for stack overflows. Used from
 // Top::StackOverflow().
 const kStackOverflowBoilerplate = MakeRangeError('stack_overflow', []);