RFR [9] 8156824: com.sun.jndi.ldap.pool.PoolCleaner should clear its context class loader

[Chris Hegarty]

Another issue where an internal platform thread is unnecessarily
retaining a reference to its creating thread’s context class loader.
In this case, it appears to be safe to use an InnocuousThread,
which will have a null context class loader.

http://cr.openjdk.java.net/~chegar/8156824/01/
https://bugs.openjdk.java.net/browse/JDK-8156824

It’s not clear to me why the construction was not always in a
privileged block, maybe “modifyThread” was assumed. We now
definitely need a privileged block as the context class loader is
being set.

-Chris.