Partially implemented in https://github.com/brmeyer/hibernate-orm/tree/metamodel_HHH-8118. For the most part, it's a matter of wiring the BindingContext or ServiceRegistry to many chains.

Areas still needing work:

1.) Dialects. Add ServiceRegistry to the static methods and the constructors?
2.) org.hibernate.engine.jdbc.*Proxy#getProxyClassLoader()
3.) org.hibernate.type. A few types do class lookups.

org.hibernate.cfg, org.hibernate.internal.util.xml, org.hibernate.mapping, etc. were ignored since they'll be removed or repurposed in 5.0.