Implement generalized function types.

pkg/front_end/tool/_fasta/generate_messages.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.
 
 import 'dart:io';
 
 import 'dart:isolate';
 
 import 'package:yaml/yaml.dart' show loadYaml;
 
@@ skipping 104 matching lines @@
   List<String> messageArguments = <String>[];
   messageArguments.add(interpolate("message", template));
   if (tip != null) {
     messageArguments.add(interpolate("tip", tip));
   }
   messageArguments.add("arguments: { ${arguments.join(', ')} }");
 
   return """
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 const FastaCode<_$name> code$name =
-    const FastaCode<_$name>(${codeArguments.join(', ')});
+    const FastaCode<_$name>(\"$name\", ${codeArguments.join(', ')});
 
 typedef FastaMessage _$name(${parameters.join(', ')});
 
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 FastaMessage _format$name(${parameters.join(', ')}) {
   ${conversions.join('\n  ')}
   return new FastaMessage(
      uri,
      charOffset,
      code$name,
      ${messageArguments.join(', ')});
 }
 """;
 }