[CRD iOS] Refactor an interface for RemotingAuthorization

remoting/ios/domain/user_info.h

 // Copyright 2017 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.
 
 #ifndef REMOTING_IOS_DOMAIN_USER_INFO_H_
 #define REMOTING_IOS_DOMAIN_USER_INFO_H_
 
 #import <Foundation/Foundation.h>
 
 // A detail record for a Remoting User.
 // TODO(nicholss): This is not the final object yet.
 @interface UserInfo : NSObject
 
 @property(nonatomic, copy) NSString* userId;
 @property(nonatomic, copy) NSString* userFullName;
 @property(nonatomic, copy) NSString* userEmail;
+// TODO(yuweih): SSO doesn't use a refresh token and it should not be used to
+// decide whether the UserInfo is authenticated.
 @property(nonatomic, copy) NSString* refreshToken;
 
 // Convert a json blob into a |UserInfo| object. Most useful for test.
 // TODO(nicholss): Might move this out into a catagory.
 + (UserInfo*)parseListFromJSON:(NSMutableData*)data;
 
 // This returns the authenticated state of the this user info object.
 - (BOOL)isAuthenticated;
 // Compare two |UserInfo| objects.
 - (NSComparisonResult)compare:(UserInfo*)user;
 
 @end
 
 #endif  //  REMOTING_IOS_DOMAIN_USER_INFO_H_