We need the ehrAccess which is required, and the EhrAccess needs
AccessControlSettings (also required), which is nowhere defined in the
specs (I think yet to come)
(required means, throws an Exception if not there)
For the question, I suggest you create instance of EHRAccess without AccessControlSettings for the time being (it is an optional attribute according to the latest spec). There is on-going working regarding AccessControlSettings class.
The current EHR class on the Trunk needs an update to include EHRAccess. But EHRAccess itself needs to have a reference to AccessControlSettings to be complete.