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

chrome/browser/chromeos/policy/user_cloud_policy_store_chromeos_unittest.cc

 // 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.
 
 #include "chrome/browser/chromeos/policy/user_cloud_policy_store_chromeos.h"
 
 #include <stdint.h>
 
 #include <vector>
 
@@ skipping 50 matching lines @@
     EXPECT_CALL(cryptohome_client_,
                 GetSanitizedUsername(PolicyBuilder::kFakeUsername, _))
         .Times(AnyNumber())
         .WillRepeatedly(
             SendSanitizedUsername(chromeos::DBUS_METHOD_CALL_SUCCESS,
                                   kSanitizedUsername));
 
     ASSERT_TRUE(tmp_dir_.CreateUniqueTempDir());
     store_.reset(new UserCloudPolicyStoreChromeOS(
         &cryptohome_client_, &session_manager_client_, loop_.task_runner(),
-        PolicyBuilder::kFakeUsername, user_policy_dir(), token_file(),
-        policy_file()));
+        AccountId::FromUserEmail(PolicyBuilder::kFakeUsername),
+        user_policy_dir(), token_file(), policy_file()));
     store_->AddObserver(&observer_);
 
     // Install the initial public key, so that by default the validation of
     // the stored/loaded policy blob succeeds.
     std::vector<uint8_t> public_key;
     ASSERT_TRUE(policy_.GetSigningKey()->ExportPublicKey(&public_key));
     StoreUserPolicyKey(public_key);
 
     policy_.payload().mutable_homepagelocation()->set_value(kDefaultHomepage);
     policy_.Build();
@@ skipping 588 matching lines @@
   Mock::VerifyAndClearExpectations(&cryptohome_client_);
 
   EXPECT_FALSE(store_->policy());
   EXPECT_TRUE(store_->policy_map().empty());
   EXPECT_EQ(CloudPolicyStore::STATUS_VALIDATION_ERROR, store_->status());
 }
 
 }  // namespace
 
 }  // namespace policy