Remove library tags, they aren't needed

lib/src/codegen/code_generator.dart

Index: lib/src/codegen/code_generator.dart
diff --git a/lib/src/codegen/code_generator.dart b/lib/src/codegen/code_generator.dart
index aeac3d310db56edd62a4e74ebb96a98cb18fa3d3..c559a415ce2f9496d3cec84444353d0939493ab8 100644
--- a/lib/src/codegen/code_generator.dart
+++ b/lib/src/codegen/code_generator.dart
@@ -2,8 +2,6 @@
 // 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 dev_compiler.src.codegen.code_generator;
-
 import 'package:analyzer/src/generated/element.dart'
     show CompilationUnitElement, LibraryElement;
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;