Move //mojo/services/X/public/... to //mojo/services/X/... (part 1).

mojo/services/authentication/interfaces/authentication.mojom

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [DartPackage="mojo_services", JavaPackage="org.chromium.mojo.authentication"]
 module authentication;
 
 // Interface to handle user identity and authentication tokens.
 // TODO(qsr): This API only handles google accounts at this time. It will need
 //            to be extended to allow generic account manager on the platform.
 interface AuthenticationService {
   // Requests a Google account to use. In case of success, error will be null.
   // In case of error, username will be null and error will contain a
   // description of the error. If |return_last_selected| is true and the client
   // application already selected an account, the same account will be returned
   // without user intervention.
   SelectAccount(bool return_last_selected) => (string? username, string? error);
 
   // Requests an oauth2 token for the given Google account with the given
   // scopes.  In case of error, username will be null and error will contain a
   // description of the error.
   GetOAuth2Token(string username, array<string> scopes) =>
       (string? token, string? error);
 
   // Requests to clear a previously acquired token. This should be called when a
   // token is refused by a server component before requesting a new token to
   // clear the token from any cache.
   ClearOAuth2Token(string token);
 };