[runtime] [proxy] removing JSFunctionProxy and related code.

src/js/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.
 
 (function(global, utils) {
 
 %CheckIsBootstrapping();
 
 // ----------------------------------------------------------------------------
 // Imports
@@ skipping 1524 matching lines @@
   var name = %FunctionGetName(func);
   if (name) {
     // Mimic what KJS does.
     return 'function ' + name + '() { [native code] }';
   }
 
   return 'function () { [native code] }';
 }
 
 function FunctionSourceString(func) {
-  while (%IsJSFunctionProxy(func)) {
-    func = %GetCallTrap(func);
-  }
-
   if (!IS_FUNCTION(func)) {
     throw MakeTypeError(kNotGeneric, 'Function.prototype.toString');
   }
 
   if (%FunctionHidesSource(func)) {
     return NativeCodeFunctionSourceString(func);
   }
 
   var classSource = %ClassGetSourceCode(func);
   if (IS_STRING(classSource)) {
@@ skipping 181 matching lines @@
 
 %InstallToContext([
   "global_eval_fun", GlobalEval,
   "object_value_of", ObjectValueOf,
   "object_to_string", ObjectToString,
   "object_get_own_property_descriptor", ObjectGetOwnPropertyDescriptor,
   "to_complete_property_descriptor", ToCompletePropertyDescriptor,
 ]);
 
 })