MULE-7865 - adding oauth 2.0 authorization code grant type support

Yes, it does. Given the nature of an object store I don't think we should provide that functionality. An object store can be a persistent object store and allowing the user of this class to call that method would will introduce big issues. 

I can change the adapter and define a different interface which is not a map but the map can be used in a lot of different context that do not require the unsupported methods.