Constant top-level variables should not have setters.

pkg/analyzer/lib/src/generated/resolver.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 engine.resolver;
 
 import "dart:math" as math;
 import 'dart:collection';
 
 import 'package:analyzer/src/generated/utilities_collection.dart';
@@ skipping 3174 matching lines @@
       if (_inFieldContext) {
         (variable as FieldElementImpl).static = _matches(
             (node.parent.parent as FieldDeclaration).staticKeyword,
             sc.Keyword.STATIC);
       }
       PropertyAccessorElementImpl getter =
           new PropertyAccessorElementImpl.forVariable(variable);
       getter.getter = true;
       _currentHolder.addAccessor(getter);
       variable.getter = getter;
-      if (!isFinal) {
+      if (!isConst && !isFinal) {
         PropertyAccessorElementImpl setter =
             new PropertyAccessorElementImpl.forVariable(variable);
         setter.setter = true;
         ParameterElementImpl parameter =
             new ParameterElementImpl("_${variable.name}", variable.nameOffset);
         parameter.synthetic = true;
         parameter.parameterKind = ParameterKind.REQUIRED;
         setter.parameters = <ParameterElement>[parameter];
         _currentHolder.addAccessor(setter);
         variable.setter = setter;
@@ skipping 12468 matching lines @@
    * library.
    */
   final HashSet<String> members = new HashSet<String>();
 
   /**
    * Names of resolved or unresolved class members that are read in the
    * library.
    */
   final HashSet<String> readMembers = new HashSet<String>();
 }