Added tag jdk8u20-b21 for changeset e20b97814618
diff --git a/hotspot/.hgtags b/hotspot/.hgtags
index 66fe6fc..88f3cd4 100644
--- a/hotspot/.hgtags
+++ b/hotspot/.hgtags
@@ -477,3 +477,4 @@
 b15553cde967dfd7781a4a5c669e4cb7db734317 jdk8u20-b19
 4f18dea0312d601d0515976bc0c643ea7acc829d hs25.20-b20
 9e4d27da4ac04c6e19291087f7c68a5c5803c7ca jdk8u20-b20
+4828415ebbf11e205dcc08e97ad5ae7dd03522f9 jdk8u20-b21