Handle calls to redirecting factories.

tests/compiler/dart2js/kernel/impact_test.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library dart2js.kernel.impact_test;
 
 import 'dart:async';
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/commandline_options.dart';
 import 'package:compiler/src/common.dart';
@@ skipping 56 matching lines @@
   testLocalFunctionInvoke();
   testLocalFunctionGet();
   testInvokeIndex(null);
   testInvokeIndexSet(null);
   testAssert();
   testAssertWithMessage();
   testFactoryInvoke();
   testFactoryInvokeGeneric();
   testFactoryInvokeGenericRaw();
   testFactoryInvokeGenericDynamic();
+  testRedirectingFactoryInvoke();
+  testRedirectingFactoryInvokeGeneric();
+  testRedirectingFactoryInvokeGenericRaw();
+  testRedirectingFactoryInvokeGenericDynamic();
 }
 
 testEmpty() {}
 testNull() => null;
 testTrue() => true;
 testFalse() => false;
 testInt() => 42;
 testDouble() => 37.5;
 testString() => 'foo';
 testStringInterpolation() => '${0}';
@@ skipping 104 matching lines @@
 }
 testFactoryInvokeGeneric() {
   new GenericClass<int, String>.fact();
 }
 testFactoryInvokeGenericRaw() {
   new GenericClass.fact();
 }
 testFactoryInvokeGenericDynamic() {
   new GenericClass<dynamic, dynamic>.fact();
 }
+testRedirectingFactoryInvoke() {
+  new Class.redirect();
+}
+testRedirectingFactoryInvokeGeneric() {
+  new GenericClass<int, String>.redirect();
+}
+testRedirectingFactoryInvokeGenericRaw() {
+  new GenericClass.redirect();
+}
+testRedirectingFactoryInvokeGenericDynamic() {
+  new GenericClass<dynamic, dynamic>.redirect();
+}
 ''',
   'helper.dart': '''
 class Class {
+  Class.generative();
   factory Class.fact() => null;
+  factory Class.redirect() = Class.generative;
 }
 class GenericClass<X, Y> {
+  GenericClass.generative();
   factory GenericClass.fact() => null;
+  factory GenericClass.redirect() = GenericClass.generative;
 }
 ''',
 };
 
 main(List<String> args) {
   asyncTest(() async {
     enableDebugMode();
     Uri entryPoint = Uri.parse('memory:main.dart');
     Compiler compiler = compilerFor(
         entryPoint: entryPoint,
@@ skipping 48 matching lines @@
         // we cannot tell the diferrence.
         builder.registerFeature(Feature.STRING_INTERPOLATION);
         builder.registerFeature(Feature.STRING_JUXTAPOSITION);
         break;
       default:
     }
   }
   impact.nativeData.forEach(builder.registerNativeData);
   return builder;
 }