Use orNull instead of explicit null default

Change-Id: I57151b924f9740aaa4d17bd1b0caf2a9ef96278d
diff --git a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala
index 9266b07..28c5ebe 100644
--- a/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala
+++ b/src/test/scala/com/googlesource/gerrit/plugins/analytics/test/CommitStatisticsCommentLinkSpec.scala
@@ -32,8 +32,8 @@
   def createCommentLinkInfo(pattern: String, link: Option[String] = None, html: Option[String] = None) = {
     val info = new CommentLinkInfo
     info.`match` = pattern
-    info.link = link.getOrElse(null)
-    info.html = html.getOrElse(null)
+    info.link = link.orNull
+    info.html = html.orNull
     info
   }