dart2js cps: Fix return type for native functions.

pkg/compiler/lib/src/cps_ir/cps_ir_nodes.dart

 // Copyright (c) 2013, 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.ir_nodes;
 
 import 'dart:collection';
 import 'cps_fragment.dart' show CpsFragment;
 import '../constants/values.dart' as values;
 import '../dart_types.dart' show DartType, InterfaceType, TypeVariableType;
 import '../elements/elements.dart';
@@ skipping 1511 matching lines @@
   bool get isSafeForElimination => true;
   bool get isSafeForReordering => true;
 
   void setParentPointers() {
     _setParentsOnList(arguments, this);
   }
 }
 
 class ForeignCode extends UnsafePrimitive {
   final js.Template codeTemplate;
-  final TypeMask type;
+  final TypeMask storedType;
   final List<Reference<Primitive>> arguments;
   final native.NativeBehavior nativeBehavior;
   final FunctionElement dependency;
 
-  ForeignCode(this.codeTemplate, this.type, List<Primitive> arguments,
+  ForeignCode(this.codeTemplate, this.storedType, List<Primitive> arguments,
       this.nativeBehavior, {this.dependency})
       : this.arguments = _referenceList(arguments);
 
   accept(Visitor visitor) => visitor.visitForeignCode(this);
 
   bool get hasValue => true;
 
   void setParentPointers() {
     _setParentsOnList(arguments, this);
   }
@@ skipping 1282 matching lines @@
     plug(new Branch.loose(_definitions.getCopy(node.condition),
         _copies[node.trueContinuation.definition],
         _copies[node.falseContinuation.definition])
       ..isStrictCheck = node.isStrictCheck);
   }
 
   visitUnreachable(Unreachable node) {
     plug(new Unreachable());
   }
 }