Update notes for submitted changes

* Use RefMap instead of HashMap

47/e37b0fa4c91aa0fe3edfc298e93ddeed4c5473

@@ -0,0 +1,7 @@
+Code-Review+2: Jonathan Nieder <jrn@google.com>
+Verified+1: Jonathan Nieder <jrn@google.com>
+Submitted-by: Jonathan Nieder <jrn@google.com>
+Submitted-at: Wed, 20 Mar 2019 19:27:27 -0400
+Reviewed-on: https://git.eclipse.org/r/139076
+Project: jgit/jgit
+Branch: refs/heads/master