Add library tags to allow Dartium to run the crypto tests.

tests/lib/crypto/hmac_sha1_test.dart

Index: tests/lib/crypto/hmac_sha1_test.dart
diff --git a/tests/lib/crypto/hmac_sha1_test.dart b/tests/lib/crypto/hmac_sha1_test.dart
index f62b1127868dc649d3464946b8903dc636eee15a..7533224b3a55ef0d60508e7a086c817e51121c2b 100644
--- a/tests/lib/crypto/hmac_sha1_test.dart
+++ b/tests/lib/crypto/hmac_sha1_test.dart
@@ -2,6 +2,9 @@
 // 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 tag to allow the test to run on Dartium.
+#library('hmac_sha1_test');
+
 // TODO(ager): Replace with "dart:crypto" when ready.
 #import("../../../lib/crypto/crypto.dart");