Request for approval for CR 7049079 - NTSYSTEM CLASS IS LEAKING 3 WINDOWS TOKENS

[Seán Coffey]

This is a forward port of a fix already in jdk5 & jdk6.

NTSystem() obtains a native Token instance for each constructor call.
This is unnecessary and Token instances should only be requested when
called for, i.e. at getImpersonationToken() time.

No auto testcase but fix has been verified though use of the MS handle
tool and a simple java testcase.

Jdk 8 code review thread : 
http://mail.openjdk.java.net/pipermail/security-dev/2011-September/003736.html

Fix has just gone into jdk8 also and changeset will be identical to that :
http://hg.openjdk.java.net/jdk8/tl-gate/jdk/rev/946e3b786d2d

regards,
Sean.