ChromeOS cryptohome should be able to use gaia id as user identifier.

chromeos/cryptohome/homedir_methods.cc

 // Copyright 2014 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.
 
 #include "chromeos/cryptohome/homedir_methods.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/bind.h"
@@ skipping 80 matching lines @@
     if (it->number)
       entry->set_number(*it->number);
     if (it->bytes)
       entry->set_bytes(*it->bytes);
   }
 }
 
 // Fill identification protobuffer.
 void FillIdentificationProtobuf(const Identification& id,
                                 cryptohome::AccountIdentifier* id_proto) {
-  id_proto->set_email(id.user_id);
+  id_proto->set_account_id(id.id());
 }
 
 // Fill authorization protobuffer.
 void FillAuthorizationProtobuf(const Authorization& auth,
                                cryptohome::AuthorizationRequest* auth_proto) {
   Key* key = auth_proto->mutable_key();
   if (!auth.label.empty()) {
     key->mutable_data()->set_label(auth.label);
   }
   key->set_secret(auth.key);
@@ skipping 187 matching lines @@
     cryptohome::AccountIdentifier id_proto;
     cryptohome::AuthorizationRequest auth_proto;
     cryptohome::UpdateKeyRequest pb_update_key;
 
     FillIdentificationProtobuf(id, &id_proto);
     FillAuthorizationProtobuf(auth, &auth_proto);
     FillKeyProtobuf(new_key, pb_update_key.mutable_changes());
     pb_update_key.set_authorization_signature(signature);
 
     DBusThreadManager::Get()->GetCryptohomeClient()->UpdateKeyEx(
-        id_proto,
-        auth_proto,
-        pb_update_key,
+        id_proto, auth_proto, pb_update_key,
         base::Bind(&HomedirMethodsImpl::OnBaseReplyCallback,
-                   weak_ptr_factory_.GetWeakPtr(),
-                   callback));
+                   weak_ptr_factory_.GetWeakPtr(), callback));
+  }
+
+  void RenameCryptohome(const Identification& id_from,
+                        const Identification& id_to,
+                        const Callback& callback) override {
+    cryptohome::AccountIdentifier id_from_proto;
+    cryptohome::AccountIdentifier id_to_proto;
+
+    FillIdentificationProtobuf(id_from, &id_from_proto);
+    FillIdentificationProtobuf(id_to, &id_to_proto);
+
+    DBusThreadManager::Get()->GetCryptohomeClient()->RenameCryptohome(
+        id_from_proto, id_to_proto,
+        base::Bind(&HomedirMethodsImpl::OnBaseReplyCallback,
+                   weak_ptr_factory_.GetWeakPtr(), callback));
   }
 
  private:
   void OnGetKeyDataExCallback(const GetKeyDataCallback& callback,
                               chromeos::DBusMethodCallStatus call_status,
                               bool result,
                               const BaseReply& reply) {
     if (call_status != chromeos::DBUS_METHOD_CALL_SUCCESS) {
       callback.Run(false, MOUNT_ERROR_FATAL, std::vector<KeyDefinition>());
       return;
@@ skipping 161 matching lines @@
   }
   delete g_homedir_methods;
   g_homedir_methods = NULL;
   VLOG(1) << "HomedirMethods Shutdown completed";
 }
 
 // static
 HomedirMethods* HomedirMethods::GetInstance() { return g_homedir_methods; }
 
 }  // namespace cryptohome