[8u40] please approve 8060688: Nashorn: Generated script class name fails --verify-code for names with special chars

[A. Sundararajan]

Please approve.

Bug: https://bugs.openjdk.java.net/browse/JDK-8060688
jdk9 review thread: 
http://mail.openjdk.java.net/pipermail/nashorn-dev/2014-October/003666.html
jdk8u-dev webrev: http://cr.openjdk.java.net/~sundar/8060688/8u40/webrev.00/

This is backported from jdk9 'as is' except for the modular source 
layout difference.

Thanks
-Sundar