Revert "filter cross context eval"

src/generator.js

 // Copyright 2013 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.
 
 "use strict";
 
 // This file relies on the fact that the following declarations have been made
 // in runtime.js:
 // var $Function = global.Function;
 
@@ skipping 30 matching lines @@
   if (%_IsConstructCall()) {
     throw MakeTypeError('not_constructor', ['GeneratorFunctionPrototype']);
   }
 }
 
 function GeneratorFunctionConstructor(arg1) {  // length == 1
   var source = NewFunctionString(arguments, 'function*');
   var global_proxy = %GlobalProxy(global);
   // Compile the string in the constructor and not a helper so that errors
   // appear to come from here.
-  var f = %CompileString(source, true);
-  if (!IS_FUNCTION(f)) return f;
-  f = %_CallFunction(global_proxy, f);
+  var f = %_CallFunction(global_proxy, %CompileString(source, true));
   %FunctionMarkNameShouldPrintAsAnonymous(f);
   return f;
 }
 
 
 function SetUpGenerators() {
   %CheckIsBootstrapping();
 
   // Both Runtime_GeneratorNext and Runtime_GeneratorThrow are supported by
   // neither Crankshaft nor TurboFan, disable optimization of wrappers here.
@@ skipping 14 matching lines @@
       GeneratorFunctionPrototype, DONT_ENUM | DONT_DELETE | READ_ONLY);
   %InternalSetPrototype(GeneratorFunctionPrototype, $Function.prototype);
   %SetCode(GeneratorFunctionPrototype, GeneratorFunctionPrototypeConstructor);
   %AddNamedProperty(GeneratorFunctionPrototype, "constructor",
       GeneratorFunction, DONT_ENUM | DONT_DELETE | READ_ONLY);
   %InternalSetPrototype(GeneratorFunction, $Function);
   %SetCode(GeneratorFunction, GeneratorFunctionConstructor);
 }
 
 SetUpGenerators();