RFR 8048073: Cannot read ccache entry with a realm-less service name

[Wang Weijun]

Please review the fix at

   http://cr.openjdk.java.net/~weijun/8048073/webrev.00/

Running native krb5 could generate a ccache file like this

  Valid starting     Expires            Service principal
  06/25/14 14:05:06  06/26/14 00:05:06  krbtgt/K1 at K1
  06/25/14 14:12:35  06/26/14 00:05:06  HTTP/localhost@
  06/25/14 14:12:35  06/26/14 00:05:06  HTTP/localhost at K1

Please note the 2nd ticket has a service principal with no realm. I guess it's a result of kerberos referral. Since OpenJDK does not support referral (yet), the PricipalName always has a realm and reading such a ccache throws out an exception. After this fix such entries are ignored and Java's klist would show

  [1]  Service Principal:  krbtgt/K1 at K1
       Valid starting:     Jun 25, 2014 14:05:06
       Expires:            Jun 26, 2014 00:05:06
  [2]  Service Principal:  HTTP/localhost at K1
       Valid starting:     Jun 25, 2014 14:12:35
       Expires:            Jun 26, 2014 00:05:06

Thanks
Max