8211825: ModuleLayer.defineModulesWithXXX does not setup delegation when module reads automatic module

[Alan Bateman]

This is the issue that Thomas Watson brought up here on Friday. If 
defineModulesWithXXX is used to create a module layer and it contains a 
module that reads an automatic module mapped to a different class loader 
(same layer or parent layer) then the class loader delegation isn't 
setup.  This scenario requires special handling the module descriptor 
for automatic modules don't declare any exports.

The changes to fix the issue are here:
   http://cr.openjdk.java.net/~alanb/8211825/webrev/index.html

Note that

-Alan