Add getIdToken getUser to OidcUser

Fixes gh-4748

oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/oidc/user/DefaultOidcUser.java

@@ -69,10 +69,12 @@ public class DefaultOidcUser extends DefaultOAuth2User implements OidcUser {
 		return this.getAttributes();
 	}
 
+	@Override
 	public OidcIdToken getIdToken() {
 		return this.idToken;
 	}
 
+	@Override
 	public OidcUserInfo getUserInfo() {
 		return this.userInfo;
 	}

oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/oidc/user/OidcUser.java

@@ -64,4 +64,8 @@ public interface OidcUser extends OAuth2User, IdTokenClaimAccessor {
 		claims.putAll(idToken.getClaims());
 		return claims;
 	}
+
+	OidcUserInfo getUserInfo();
+
+	OidcIdToken getIdToken();
 }