Support specifying Adjustment state for fetch requests

I've made a few small changes to support specifying Adjustment state for fetch requests. 

I also increased the visibility of doGET because with this visibility I would have been able to append the state parameter to a fetch URL without modifying the client code at all. 
I understand the convenience of this but it makes me really nervous to expose it as part of the API since it's really an implementation detail. Besides, what about `PUT`, `POST`, etc.?