Use common.dart to re-export commonly used entities.

pkg/compiler/lib/src/parser/partial_parser.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.
 
 library dart2js.parser.partial;
 
-import '../diagnostics/messages.dart' show
-    MessageKind;
+import '../common.dart';
 import '../util/characters.dart' as Characters show
     $CLOSE_CURLY_BRACKET;
 import '../tokens/token.dart' show
     BeginGroupToken,
     ErrorToken,
     Token;
 import '../tokens/token_constants.dart' as Tokens show
     EOF_TOKEN;
 
 import 'listener.dart' show
@@ skipping 154 matching lines @@
         return token;
       }
       return listener.unexpected(token);
     }
     BeginGroupToken beginGroupToken = token;
     Token endToken = beginGroupToken.endGroup;
     listener.endFormalParameters(0, token, endToken);
     return endToken.next;
   }
 }