Use a service to create device management backends.

chrome/browser/policy/profile_policy_context.h

Index: chrome/browser/policy/profile_policy_context.h
diff --git a/chrome/browser/policy/profile_policy_context.h b/chrome/browser/policy/profile_policy_context.h
new file mode 100644
index 0000000000000000000000000000000000000000..b343e1566db1229589892d19e62acfd6a4445059
--- /dev/null
+++ b/chrome/browser/policy/profile_policy_context.h
@@ -0,0 +1,51 @@
+// Copyright (c) 2010 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_PROFILE_POLICY_CONTEXT_H_
+#define CHROME_BROWSER_POLICY_PROFILE_POLICY_CONTEXT_H_
+#pragma once
+
+#include "base/scoped_ptr.h"
+
+class Profile;
+
+namespace policy {
+
+class DeviceManagementPolicyProvider;
+class DeviceManagementService;
+
+// This class is a container for the profile-specific policy bits located in the
+// profile. Since the context owns the policy provider, it's vital that it gets
+// initialized before the profile's prefs and destroyed after the prefs are
+// gone.

[Nico, 2010/11/22 11:06:06]

The comments on |Initialize()| and |Shutdown()| suggest that you mean "…vital
that it gets initialized _after_ the profile's prefs and destroyed _before_ the
prefs are gone." (right?)

[Mattias Nissler (ping if slow), 2010/11/22 12:35:39]

No, actually the comment is correct. The ProfilePolicyContext is a dependency of
the PrefService, so it needs to be constructed before the the prefs and
destroyed after the prefs.

Initialize and Shutdown are there to handle the parts of the context that are
dependent on other profile stuff that gets started later / shut down earlier.

[Nico, 2010/11/22 12:40:16]

Ah! I mixed up the profile's pref and the profile itself.

+class ProfilePolicyContext {
+ public:
+  explicit ProfilePolicyContext(Profile* profile);
+  ~ProfilePolicyContext();
+
+  // Initializes the context. Should be called only after the profile's request
+  // context is up.
+  void Initialize();
+
+  // Shuts the context down. This must be called before the networking
+  // infrastructure in the profile goes away.
+  void Shutdown();
+
+  // Get the policy provider.
+  DeviceManagementPolicyProvider* GetDeviceManagementPolicyProvider();
+
+ private:
+  // The profile this context is associated with.
+  Profile* profile_;
+
+  // The device management service.
+  scoped_ptr<DeviceManagementService> device_management_service_;

[Nico, 2010/11/22 11:06:06]

No getter for this guy?

[Mattias Nissler (ping if slow), 2010/11/22 12:35:39]

Not needed at the moment. GetDeviceManagementPolicyProvider needs it to create
the provider.

+
+  // Our provider.
+  scoped_ptr<DeviceManagementPolicyProvider> device_management_policy_provider_;
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_POLICY_PROFILE_POLICY_CONTEXT_H_