DeviceSettingsProvider's write path uses OwnerSettingsService now.

chrome/browser/chromeos/ownership/owner_settings_service_chromeos.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 CHROME_BROWSER_CHROMEOS_OWNERSHIP_OWNER_SETTINGS_SERVICE_CHROMEOS_H_
 #define CHROME_BROWSER_CHROMEOS_OWNERSHIP_OWNER_SETTINGS_SERVICE_CHROMEOS_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 29 matching lines @@
                                      public DeviceSettingsService::Observer {
  public:
   virtual ~OwnerSettingsServiceChromeOS();
 
   void OnTPMTokenReady(bool tpm_token_enabled);
 
   // ownership::OwnerSettingsService implementation:
   virtual bool HandlesSetting(const std::string& setting) override;
   virtual bool Set(const std::string& setting,
                    const base::Value& value) override;
+  virtual bool SetPolicy(
+      scoped_ptr<enterprise_management::PolicyData> policy) override;
 
   // NotificationObserver implementation:
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) override;
 
   // SessionManagerClient::Observer:
   virtual void OwnerKeySet(bool success) override;
 
   // DeviceSettingsService::Observer:
@@ skipping 89 matching lines @@
   base::WeakPtrFactory<OwnerSettingsServiceChromeOS> weak_factory_;
 
   base::WeakPtrFactory<OwnerSettingsServiceChromeOS> store_settings_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OwnerSettingsServiceChromeOS);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_OWNERSHIP_OWNER_SETTINGS_SERVICE_CHROMEOS_H_