RFR 8138638: Security tests using jdk/test/sun/security/krb5/auto/KDC.java fail intermittently with OutOfMemoryError

[Wang Weijun]

Please review the fix at

  http://cr.openjdk.java.net/~weijun/8138638/webrev.00/

It looks like the TCP server should be accessed in the failed tests. Maybe a 
random process happens to connect to the server? This code change will ignore 
the unknown request.

Thanks
Max