[runtime] Also migrate the Function and GeneratorFunction constructors to C++.

src/js/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.
 
 (function(global, utils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var GeneratorFunctionPrototype = utils.ImportNow("GeneratorFunctionPrototype");
 var GeneratorFunction = utils.ImportNow("GeneratorFunction");
 var GlobalFunction = global.Function;
 var MakeTypeError;
-var NewFunctionString;
 var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
 
 utils.Import(function(from) {
   MakeTypeError = from.MakeTypeError;
-  NewFunctionString = from.NewFunctionString;
 });
 
 // ----------------------------------------------------------------------------
 
 // Generator functions and objects are specified by ES6, sections 15.19.3 and
 // 15.19.4.
 
 function GeneratorObjectNext(value) {
   if (!IS_GENERATOR(this)) {
     throw MakeTypeError(kIncompatibleMethodReceiver,
@@ skipping 37 matching lines @@
     }
   } else if (continuation == 0) {
     // Generator is already closed.
     throw exn;
   } else {
     // Generator is running.
     throw MakeTypeError(kGeneratorRunning);
   }
 }
 
-
-function GeneratorFunctionConstructor(arg1) {  // length == 1
-  var source = NewFunctionString(arguments, 'function*');
-  var global_proxy = %GlobalProxy(GeneratorFunctionConstructor);
-  // Compile the string in the constructor and not a helper so that errors
-  // appear to come from here.
-  var func = %_Call(%CompileString(source, true), global_proxy);
-  // Set name-should-print-as-anonymous flag on the ShareFunctionInfo and
-  // ensure that |func| uses correct initial map from |new.target| if
-  // it's available.
-  return %CompleteFunctionConstruction(func, GeneratorFunction, new.target);
-}
-
 // ----------------------------------------------------------------------------
 
 // Both Runtime_GeneratorNext and Runtime_GeneratorThrow are supported by
 // neither Crankshaft nor TurboFan, disable optimization of wrappers here.
 %NeverOptimizeFunction(GeneratorObjectNext);
 %NeverOptimizeFunction(GeneratorObjectThrow);
 
 // Set up non-enumerable functions on the generator prototype object.
 var GeneratorObjectPrototype = GeneratorFunctionPrototype.prototype;
 utils.InstallFunctions(GeneratorObjectPrototype,
                        DONT_ENUM,
                       ["next", GeneratorObjectNext,
                        "throw", GeneratorObjectThrow]);
 
 %AddNamedProperty(GeneratorObjectPrototype, "constructor",
     GeneratorFunctionPrototype, DONT_ENUM | READ_ONLY);
 %AddNamedProperty(GeneratorObjectPrototype,
     toStringTagSymbol, "Generator", DONT_ENUM | READ_ONLY);
 %InternalSetPrototype(GeneratorFunctionPrototype, GlobalFunction.prototype);
 %AddNamedProperty(GeneratorFunctionPrototype,
     toStringTagSymbol, "GeneratorFunction", DONT_ENUM | READ_ONLY);
 %AddNamedProperty(GeneratorFunctionPrototype, "constructor",
     GeneratorFunction, DONT_ENUM | READ_ONLY);
 %InternalSetPrototype(GeneratorFunction, GlobalFunction);
-%SetCode(GeneratorFunction, GeneratorFunctionConstructor);
 
 })