Check emitter constants and fix tearOffName for JConstructorBody

pkg/compiler/lib/src/js_emitter/model.dart

 // Copyright (c) 2014, 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.new_js_emitter.model;
 
 import '../constants/values.dart' show ConstantValue;
 import '../deferred_load.dart' show OutputUnit;
 import '../elements/entities.dart';
 import '../js/js.dart' as js show Expression, Name, Statement, TokenFinalizer;
@@ skipping 374 matching lines @@
   /// Uses indicate missing information in the model.
   final MemberEntity element;
 
   /// The name of the method. If the method is a [ParameterStubMethod] for a
   /// static function, then the name can be `null`. In that case, only the
   /// [ParameterStubMethod.callName] should be used.
   final js.Name name;
   final js.Expression code;
 
   Method(this.element, this.name, this.code);
+
+  String toString() {
+    return 'method[name=${name},element=${element}'

[sra1, 2017/07/11 18:24:05]

FWIW I prefer these debug-oriented strings to have the same name as the class
and use parens and source-code-like spacing, e.g.

    Method(name=x, element=z)

rather than

    method[name=x,element=z].

If we consistently use the class name then it is easier to know where to look
for the definition.

[Johnni Winther, 2017/07/12 10:03:24]

Will change in a follow-up CL.

+        ',code=${js.nodeToString(code)}]';
+  }
 }
 
 /// A method that corresponds to a method in the original Dart program.
 abstract class DartMethod extends Method {
   final bool needsTearOff;
   final js.Name tearOffName;
   final List<ParameterStubMethod> parameterStubs;
   final bool canBeApplied;
   final bool canBeReflected;
 
@@ skipping 141 matching lines @@
   String toString() {
     return 'static_method[name=${name},element=${element}}]';
   }
 }
 
 class StaticStubMethod extends StubMethod implements StaticMethod {
   Holder holder;
   StaticStubMethod(js.Name name, this.holder, js.Expression code)
       : super(name, code);
 }