[8u40] Request for phase 2 approval: 8068889: Calling a @FunctionalInterface from JS leaks internal objects

[Attila Szegedi]

Please approve.

Bug: https://bugs.openjdk.java.net/browse/JDK-8068889
jdk9 webrev: http://cr.openjdk.java.net/~attila/8068889/webrev.00
jdk9 review thread: http://mail.openjdk.java.net/pipermail/nashorn-dev/2015-January/004092.html
Reviewers: jlaskey, sundar
Rationale: this bug is present in 8u25 and is known to cause a serious regression when upgrading from pre-8u25.

Changes apply cleanly to jdk8u40-dev after path reshuffling from modular source code layout. The change is already backported in its current form to 8u-dev.

Thanks,
 Attila.