Make function proxies work as constructors.

src/runtime.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 387 matching lines @@
 function FILTER_KEY(key) {
   var string = %ToString(key);
   if (%HasProperty(this, string)) return string;
   return 0;
 }
 
 
 function CALL_NON_FUNCTION() {
   var delegate = %GetFunctionDelegate(this);
   if (!IS_FUNCTION(delegate)) {
-    if (%IsJSFunctionProxy(this)) {
-      delegate = %GetCallTrap(this);
-    } else {
-      throw %MakeTypeError('called_non_callable', [typeof this]);
-    }
+    throw %MakeTypeError('called_non_callable', [typeof this]);
   }
   return delegate.apply(this, arguments);
 }
 
 
 function CALL_NON_FUNCTION_AS_CONSTRUCTOR() {
   var delegate = %GetConstructorDelegate(this);
   if (!IS_FUNCTION(delegate)) {
-    if (%IsJSFunctionProxy(this)) {
-      delegate = %GetConstructTrap(this);
-    } else {
-      throw %MakeTypeError('called_non_callable', [typeof this]);
-    }
+    throw %MakeTypeError('called_non_callable', [typeof this]);
   }
   return delegate.apply(this, arguments);
 }
 
 
 function CALL_FUNCTION_PROXY() {
   var arity = %_ArgumentsLength() - 1;
   var proxy = arguments[arity];  // The proxy comes in as an additional arg.
   var trap = %GetCallTrap(proxy);
   // TODO(rossberg): hm, shouldn't I be using $Function and friends?
   // But how do I get it in a builtin?
-  return global.Function.prototype.apply.call(
-    trap, this, global.Array.prototype.slice.call(arguments, 0, arity));
+  return Function.prototype.apply.call(
+    trap, this, Array.prototype.slice.call(arguments, 0, arity));
 }
 
 
-function CALL_FUNCTION_PROXY_AS_CONSTRUCTOR(proxy) {
+function CALL_FUNCTION_PROXY_AS_CONSTRUCTOR() {
+  var proxy = this;
   var trap = %GetConstructTrap(proxy);
-  var receiver = void 0;
-  if (!IS_UNDEFINED(trap)) {
-    trap = %GetCallTrap(proxy);
-    var proto = proxy.prototype;
-    if (!IS_SPEC_OBJECT(proto) && proto !== null) {
-      throw MakeTypeError("proto_object_or_null", [proto]);
-    }
-    receiver = new global.Object();
-    receiver.__proto__ = proto;
-  }
-  return global.Function.prototype.apply.call(
-    trap, this, global.Array.prototype.shift.call(arguments));
+  // TODO(rossberg): should be using $Function or a builtin somehow.
+  return Function.prototype.apply.call(trap, this, arguments);
 }
 
 
 function APPLY_PREPARE(args) {
   var length;
   // First check whether length is a positive Smi and args is an
   // array. This is the fast case. If this fails, we do the slow case
   // that takes care of more eventualities.
   if (IS_ARRAY(args)) {
     length = args.length;
@@ skipping 211 matching lines @@
   throw %MakeTypeError('cannot_convert_to_primitive', []);
 }
 
 
 // NOTE: Setting the prototype for Array must take place as early as
 // possible due to code generation for array literals.  When
 // generating code for a array literal a boilerplate array is created
 // that is cloned when running the code.  It is essential that the
 // boilerplate gets the right prototype.
 %FunctionSetPrototype($Array, new $Array(0));