8157499: Mark several tests from jdk_net as intermittently failing

Reviewed-by: chegar

jdk/test/java/net/DatagramSocket/PortUnreachable.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2013 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2016, 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
@@ -24,6 +24,7 @@
 /**
  * @test
  * @bug 4361783
+ * @key intermittent
  * @summary  Test to see if ICMP Port Unreachable on non-connected
  *           DatagramSocket causes a SocketException "socket closed"
  *           exception on Windows 2000.

jdk/test/java/net/InetAddress/IsReachableViaLoopbackTest.java

@@ -5,6 +5,7 @@ import java.util.*;
 /**
  * @test
  * @bug 8135305
+ * @key intermittent
  * @summary ensure we can't ping external hosts via loopback if
  */
 

jdk/test/java/net/MulticastSocket/TestInterfaces.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2016, 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
@@ -24,6 +24,7 @@
 /*
  * @test
  * @bug 4422122
+ * @key intermittent
  * @summary Test that MulticastSocket.getInterface returns the
  *          same InetAddress set by MulticastSocket.setInterface
  */

jdk/test/sun/net/www/http/ChunkedOutputStream/checkError.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2004, 2016, 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
@@ -24,6 +24,7 @@
 /**
  * @test
  * @bug 5054016
+ * @key intermittent
  * @run main/othervm/timeout=300 checkError
  * @summary get the failure immediately when writing individual chunks over socket fail
  */