Do we really need publicKey to be outside of the request property? #49

In this, publicKey is part of the top-level parameter.

dictionary IdentityRequestProvider {
 required DOMString protocol; // See "Protocol Registry" below
 required DOMString request;
 required DOMString publicKey;
}

Should publicKey be (opaquely, optionally and per protocol) part of request instead of IdentityRequestProvider?