Added the AutoEnrollmentClient and unit tests for it.

chrome/browser/policy/browser_policy_connector.h

 // Copyright (c) 2011 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 CHROME_BROWSER_POLICY_BROWSER_POLICY_CONNECTOR_H_
 #define CHROME_BROWSER_POLICY_BROWSER_POLICY_CONNECTOR_H_
 #pragma once
 
 #include <string>
 
@@ skipping 68 matching lines @@
                                const std::string& token,
                                TokenType token_type);
 
   // Returns true if this device is managed by an enterprise (as opposed to
   // a local owner).
   bool IsEnterpriseManaged();
 
   // Locks the device to an enterprise domain.
   EnterpriseInstallAttributes::LockResult LockDevice(const std::string& user);
 
+  // Returns the device serial number, or an empty string if not available.
+  static std::string GetSerialNumber();
+
   // Returns the enterprise domain if device is managed.
   std::string GetEnterpriseDomain();
 
   // Reset the device policy machinery. This stops any automatic retry behavior
   // and clears the error flags, so potential retries have a chance to succeed.
   void ResetDevicePolicy();
 
   // Initiates device and user policy fetches, if possible. Pending fetches
   // will be cancelled.
   void FetchCloudPolicy();
@@ skipping 79 matching lines @@
 
   // Used to convert policies to preferences.
   ConfigurationPolicyHandlerList handler_list_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPolicyConnector);
 };
 
 }  // namespace policy
 
 #endif  // CHROME_BROWSER_POLICY_BROWSER_POLICY_CONNECTOR_H_