RFR 8168075: Custom system class loader + security manager + malformed policy file = recursive initialization

[Adam Petcher]

Please review the following bug fix:

http://cr.openjdk.java.net/~apetcher/8168075/webrev.00/

This fixes a bug in which a permission check would try to load resources 
while the system class loader is being initialized. Resources cannot be 
loaded at this time, so this change ensures that the resources are 
loaded earlier.