JNI changes for modules

[Florian Weimer]

I see there's a new GetModule entry point, but I can't find anything
that interacts directly with it.

The challenge I see is that FindClass often cannot find application
classes once modules are involved.  Technically, I guess that's not a
new phenomenon and could have happened before once multiple class
loaders are involved.  However, modules seem to encourage such setups
and expose this functionality to more developers, I suppose.

Is the recommended way to use the jclass parameter of native methods
with GetModule to obtain the application module, and call
getClassLoader() and its loadClass(String) methods to get this to
work?  Isn't this a tad bit involved?  There's also an asymmetry due
to the use of source class names, unlike FindClass.