Non fatal errors on duplicated accessors

dart/pkg/compiler/lib/src/warnings.dart

 // Copyright (c) 2011, 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.
 
 part of dart2js;
 
 const DONT_KNOW_HOW_TO_FIX = "Computer says no!";
 
 /**
  * The messages in this file should meet the following guide lines:
@@ skipping 164 matching lines @@
   static const MessageKind INVALID_UNNAMED_CONSTRUCTOR_NAME = const MessageKind(
       "Unnamed constructor name must be '#{name}'.");
 
   static const MessageKind INVALID_CONSTRUCTOR_NAME = const MessageKind(
       "Constructor name must start with '#{name}'.");
 
   static const MessageKind CANNOT_RESOLVE_TYPE = const MessageKind(
       "Cannot resolve type '#{typeName}'.");
 
   static const MessageKind DUPLICATE_DEFINITION = const MessageKind(
-      "Duplicate definition of '#{name}'.");
+      "Duplicate definition of '#{name}'.",
+      howToFix: "Try to rename or remove this definition.",
+      examples: const ["""
+class C {
+  void f() {}
+  int get f => 1;
+}
+
+main() {
+  new C();
+}
+
+"""]);
 
   static const MessageKind EXISTING_DEFINITION = const MessageKind(
       "Existing definition of '#{name}'.");
 
   static const MessageKind DUPLICATE_IMPORT = const MessageKind(
       "Duplicate import of '#{name}'.");
 
   static const MessageKind HIDDEN_IMPORT = const MessageKind(
       "'#{name}' from library '#{hiddenUri}' is hidden by '#{name}' "
       "from library '#{hidingUri}'.",
@@ skipping 2242 matching lines @@
   static String convertToString(value) {
     if (value is ErrorToken) {
       // Shouldn't happen.
       return value.assertionMessage;
     } else if (value is Token) {
       value = value.value;
     }
     return '$value';
   }
 }