[8u40] approval request for 8058615: Overload resolution ambiguity involving ConsString

[A. Sundararajan]

Please approve.

Bug: https://bugs.openjdk.java.net/browse/JDK-8058615
jdk9 review thread: 
http://mail.openjdk.java.net/pipermail/nashorn-dev/2014-September/003477.html
jdk8u-dev webrev: http://cr.openjdk.java.net/~sundar/8058615/8u40/webrev.00/

Thanks,
-Sundar