Incremental compilation: set up inheritance.

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 = "";
+const DONT_KNOW_HOW_TO_FIX = "Computer says no!";
 
 /**
  * The messages in this file should meet the following guide lines:
  *
  * 1. The message should be a complete sentence starting with an uppercase
  * letter, and ending with a period.
  *
  * 2. Reserved words and embedded identifiers should be in single quotes, so
  * prefer double quotes for the complete message. For example, "The
  * class '#{className}' can't use 'super'." Notice that the word 'class' in the
@@ skipping 2216 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';
   }
 }