Get rid of all the library tags.

lib/src/crypto_utils.dart

 // Copyright (c) 2012, 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 crypto.crypto_utils;
-
 import 'base64.dart';
 
 /// Utility methods for working with message digests.
 abstract class CryptoUtils {
   /// Convert a list of bytes (for example a message digest) into a hexadecimal
   /// string.
   static String bytesToHex(List<int> bytes) {
     var result = new StringBuffer();
     for (var part in bytes) {
       result.write('${part < 16 ? '0' : ''}${part.toRadixString(16)}');
@@ skipping 21 matching lines @@
   /// Converts a [Base64-encoded][rfc] String into list of bytes.
   ///
   /// [rfc]: https://tools.ietf.org/html/rfc4648
   ///
   /// This ignores "\r\n" sequences in [input]. It accepts both URL-safe and
   /// -unsafe Base 64 encoded strings.
   ///
   /// Throws a [FormatException] if [input] contains invalid characters.
   static List<int> base64StringToBytes(String input) => BASE64.decode(input);
 }