JDK 9 RFR of JDK-8172220: Mark UserInputTest.java as intermittently failing

[joe darcy]

Hello,

The langtools test

     jdk/jshell/UserInputTest.java

has been seen to intermittently fail and should be marked accordingly; 
patch below.

Thanks,

-Joe

diff -r 4f348bd05341 test/jdk/jshell/UserInputTest.java
--- a/test/jdk/jshell/UserInputTest.java    Tue Jan 03 11:33:18 2017 +0000
+++ b/test/jdk/jshell/UserInputTest.java    Tue Jan 03 16:49:22 2017 -0800
@@ -1,5 +1,5 @@
  /*
- * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights 
reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
@@ -27,6 +27,7 @@
   * @summary Verify that the user's code can read System.in
   * @build KullaTesting TestingInputStream
   * @run testng UserInputTest
+ * @key intermittent
   */

  import java.io.IOException;