[8u] RFR 8160768: Add capability to custom resolve host/domain names within the default JNDI LDAP provider

[Zhengyu Gu]

Hi,

I would like to backport this patch to 8u for parity with Oracle 8u261.

The original patch does not apply cleanly.

Other than a couple of minor conflicts:

1) Comments in InitialDirContext.java did not apply cleanly
2) Unpatched CheckConfigs.policy files did not match

I made following modification for 8u:

1) Removed module-info.java section, it does not apply to 8u.
2) LdapDnsProvider.java and LdapDnsProviderResult.java use APIs 
(List.copyOf() and List.of()) that do not exist in jdk8. Rewrote the 
code with ArrayList<String>.
3) Removed @modules annotation in LdapDnsProviderTest.java

Additional, I need to modify langtools to get javac to take 
com.sun.jndi.ldap.spi package and complain about it.

Original bug: https://bugs.openjdk.java.net/browse/JDK-8160768
Original patch: http://hg.openjdk.java.net/jdk/jdk/rev/a609d549992a

8u jdk webrev: http://cr.openjdk.java.net/~zgu/JDK-8160768-8u/jdk/webrev.00/
8u langtools webrev: 
http://cr.openjdk.java.net/~zgu/JDK-8160768-8u/langtools/webev.00/


Test:
   jdk_other on Linux x86_64

Thanks,

-Zhengyu