Remove library tags, they aren't needed

lib/src/summary.dart

 // Copyright (c) 2015, 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.
 
 /// Summary of error messages produced by a `SummaryReporter`.
-library dev_compiler.src.summary;
 
 import 'dart:collection' show HashSet;
 
 import 'package:source_span/source_span.dart';
 
 /// Summary information computed by the DDC checker.
 abstract class Summary {
   Map toJsonMap();
 
   void accept(SummaryVisitor visitor);
@@ skipping 222 matching lines @@
   }
 
   void visitHtml(HtmlSummary html) {
     for (var msg in html.messages) {
       msg.accept(this);
     }
   }
 
   void visitMessage(MessageSummary message) {}
 }