RFR: 8025909: Lambda Library Spec Updates

[Henry Jen]

Hi,

Please kindly review the latest update on lambda library spec, and a few
minor code clean up.

Webrev and specdiff can be found at,

http://cr.openjdk.java.net/~henryjen/ccc/8025909/0/webrev
http://cr.openjdk.java.net/~henryjen/ccc/8025909/0/specdiff

This webrev also covers update that address JDK-8024179 as the spec
update explains why reported scenario is expected.

Cheers,
Henry