[8u] 8239385: KerberosTicket client name refers wrongly to sAMAccountName in AD

[Zhengyu Gu]

I would like to backport this patch to 8u, for parity with Oracle 8u271.

Original patch applies cleanly.

However, it failed to build, cause it expects 
sun.security.krb5.Config.getBooleanObject(String... keys) to be public 
method, while 8u and only 8u, it declares as private. Apparently, the 
method was partially backported and made it private.

Original bug: https://bugs.openjdk.java.net/browse/JDK-8239385
Original patch: https://hg.openjdk.java.net/jdk/jdk/rev/142d090cab77

8u webrev: http://cr.openjdk.java.net/~zgu/JDK-8239385-8u/webrev.00/

Test:
   jdk_security

Thanks,

-Zhengyu