Deprecate HOSTED_NOT_ALLOWED auth error

google_apis/gaia/google_service_auth_error.h

 // Copyright (c) 2012 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.
 
 // A GoogleServiceAuthError is immutable, plain old data representing an
 // error from an attempt to authenticate with a Google service.
 // It could be from Google Accounts itself, or any service using Google
 // Accounts (e.g expired credentials).  It may contain additional data such as
 // captcha or OTP challenges.
 
@@ skipping 56 matching lines @@
     // The service is not available; try again later.
     SERVICE_UNAVAILABLE = 7,
 
     // The password is valid but we need two factor to get a token.
     TWO_FACTOR = 8,
 
     // The requestor of the authentication step cancelled the request
     // prior to completion.
     REQUEST_CANCELED = 9,
 
-    // The user has provided a HOSTED account, when this service requires
-    // a GOOGLE account.
-    HOSTED_NOT_ALLOWED = 10,
+    // HOSTED accounts are deprecated; left in enumeration to match
+    // GoogleServiceAuthError enum in histograms.xml.
+    HOSTED_NOT_ALLOWED_DEPRECATED = 10,
 
     // Indicates the service responded to a request, but we cannot
     // interpret the response.
     UNEXPECTED_SERVICE_RESPONSE = 11,
 
     // Indicates the service responded and response carried details of the
     // application error.
     SERVICE_ERROR = 12,
 
     // The password is valid but web login is required to get a token.
@@ skipping 120 matching lines @@
                          int image_height);
 
   State state_;
   Captcha captcha_;
   SecondFactor second_factor_;
   int network_error_;
   std::string error_message_;
 };
 
 #endif  // GOOGLE_APIS_GAIA_GOOGLE_SERVICE_AUTH_ERROR_H_