Review request for JDK-8141538: Make DynamicLinker specific to a Context in Nashorn

[Sundararajan Athijegannathan]

+1

http://mail.openjdk.java.net/pipermail/nashorn-dev/2015-November/005527.html

PS. We should perhaps change that System property 
"nashorn.unstable.relink.threshold" to a Context option (now that 
DynamicLinker is context specific). It can be later - we just need a bug

Thanks
-Sundar