Make the crypto library an official dart:crypto library.

tests/lib/crypto/sha1_test.dart

Index: tests/lib/crypto/sha1_test.dart
diff --git a/tests/lib/crypto/sha1_test.dart b/tests/lib/crypto/sha1_test.dart
index af9abad490761365c4f6be082b7632644ff463e3..1985d1722430ed65f6dc2d685c6fa62e52de812e 100644
--- a/tests/lib/crypto/sha1_test.dart
+++ b/tests/lib/crypto/sha1_test.dart
@@ -5,8 +5,7 @@
 // Library tag to allow dartium to run the test.
 #library('sha1_test');
 
-// TODO(ager): Replace with "dart:crypto" when ready.
-#import("../../../lib/crypto/crypto.dart");
+#import("dart:crypto");
 
 #source('sha1_long_test_vectors.dart');
 #source('sha1_short_test_vectors.dart');