JDK-8153858 partially consolidated the logic shared between InstanceKlass::package_from_name and ClassLoader::package_from_name. Unfortunately it also caused an undetected regression in some paths due need to copy from Symbol -> resource char arrays and back again.

An empirical experiment shows we can improve performance and consolidate to a single implementation by keeping the implementation as a Symbol:

http://cr.openjdk.java.net/~redestad/scratch/pkg_lookups.00/

This reduces retired instructions on Hello World by ~400k, or ~0.4%