We should use UserID object to identify users instead of username.

components/policy/core/browser/browser_policy_connector.h

 // 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.
 
 #ifndef COMPONENTS_POLICY_CORE_BROWSER_BROWSER_POLICY_CONNECTOR_H_
 #define COMPONENTS_POLICY_CORE_BROWSER_BROWSER_POLICY_CONNECTOR_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "components/policy/core/browser/configuration_policy_handler_list.h"
 #include "components/policy/core/common/schema.h"
 #include "components/policy/core/common/schema_registry.h"
 #include "components/policy/policy_export.h"
 
 class PrefRegistrySimple;
 class PrefService;
 
 namespace net {
 class URLRequestContextGetter;
 }
 
+namespace user_manager {
+class UserID;
+}
+
 namespace policy {
 
 class ConfigurationPolicyProvider;
 class DeviceManagementService;
 class PolicyService;
 class PolicyStatisticsCollector;
 
 // The BrowserPolicyConnector keeps the browser-global (non Profile-specific)
 // policy providers, and some shared components of the policy system.
 // This is a basic implementation that gets extended by platform-specific
@@ skipping 47 matching lines @@
   // GetPolicyService. This is a static method because local state is
   // created immediately after the connector, and tests don't have a chance to
   // inject the provider otherwise. |provider| must outlive the connector, and
   // its ownership is not taken though the connector will initialize and shut it
   // down.
   static void SetPolicyProviderForTesting(
       ConfigurationPolicyProvider* provider);
 
   // Check whether a user is known to be non-enterprise. Domains such as
   // gmail.com and googlemail.com are known to not be managed. Also returns
-  // false if the username is empty.
-  static bool IsNonEnterpriseUser(const std::string& username);
+  // false if the user email is empty.
+  static bool IsNonEnterpriseUser(const user_manager::UserID& user_id);
 
   // Returns the URL for the device management service endpoint.
   static std::string GetDeviceManagementUrl();
 
   // Registers refresh rate prefs.
   static void RegisterPrefs(PrefRegistrySimple* registry);
 
  protected:
   // Builds an uninitialized BrowserPolicyConnector.
   // Init() should be called to create and start the policy components.
@@ skipping 42 matching lines @@
   scoped_ptr<PolicyStatisticsCollector> policy_statistics_collector_;
 
   scoped_ptr<DeviceManagementService> device_management_service_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPolicyConnector);
 };
 
 }  // namespace policy
 
 #endif  // COMPONENTS_POLICY_CORE_BROWSER_BROWSER_POLICY_CONNECTOR_H_