Check emitter constants and fix tearOffName for JConstructorBody

pkg/compiler/lib/src/js_model/elements.dart

 // Copyright (c) 2017, 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.js_model.elements;
 
 import '../common_elements.dart';
 import '../constants/constant_system.dart';
 import '../elements/elements.dart';
 import '../elements/entities.dart';
@@ skipping 421 matching lines @@
       : super(
             memberIndex,
             constructor.library,
             constructor.enclosingClass,
             constructor.memberName,
             constructor.parameterStructure,
             AsyncMarker.SYNC,
             isStatic: false,
             isExternal: false);
 
-  @override
-  bool get isFunction => true;
-
   String get _kind => 'constructor_body';
 }
 
 class JMethod extends JFunction {
   final bool isAbstract;
 
   JMethod(int memberIndex, JLibrary library, JClass enclosingClass, Name name,
       ParameterStructure parameterStructure, AsyncMarker asyncMarker,
       {bool isStatic, bool isExternal, this.isAbstract})
       : super(memberIndex, library, enclosingClass, name, parameterStructure,
@@ skipping 287 matching lines @@
 
   @override
   bool get isFunctionApplyUsed => _backendUsage.isFunctionApplyUsed;
 
   @override
   bool get isMirrorsUsed => _backendUsage.isMirrorsUsed;
 
   @override
   bool get isNoSuchMethodUsed => _backendUsage.isNoSuchMethodUsed;
 }