[jdk9] RFR: 8159822: Non-synchronized access to shared members of com.sun.jndi.ldap.pool.Pool

[Ivan Gerasimov]

Hello!

The Pool has a member `map`, which is accessed from different threads, 
thus the access is synchronized.
However, in some code paths (mostly in debug printing) it is accessed 
without proper synchronization, which results in intermediate 
ConcurrentModificationException when the debug output is turned on.

Would you please help review the fix?

BUGURL: https://bugs.openjdk.java.net/browse/JDK-8159822
WEBREV: http://cr.openjdk.java.net/~igerasim/8159822/00/webrev/

With kind regards,
Ivan