Add support for loading user cloud policy on desktop.

chrome/browser/policy/user_policy_signin_service.h

Index: chrome/browser/policy/user_policy_signin_service.h
diff --git a/chrome/browser/policy/user_policy_signin_service.h b/chrome/browser/policy/user_policy_signin_service.h
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+++ b/chrome/browser/policy/user_policy_signin_service.h
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+// 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.
+
+#ifndef CHROME_BROWSER_POLICY_USER_POLICY_SIGNIN_SERVICE_H_
+#define CHROME_BROWSER_POLICY_USER_POLICY_SIGNIN_SERVICE_H_
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "chrome/browser/profiles/profile_keyed_service.h"
+#include "chrome/common/net/gaia/oauth2_access_token_consumer.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+class OAuth2AccessTokenFetcher;
+class Profile;
+
+namespace base {
+class Time;
+}
+
+namespace policy {
+
+class UserCloudPolicyManager;
+
+// The UserPolicySigninService tracks when user signin/signout actions occur and
+// initializes/shuts down the UserCloudPolicyManager as required. This class is
+// not used on ChromeOS because UserCloudPolicyManager initialization is handled
+// via LoginUtils, since it must happen before profile creation.
+#if !defined(OS_CHROMEOS)

[Mattias Nissler (ping if slow), 2012/08/03 12:19:08]

Seems like this should rather use an exclude rule in chrome_browser.gypi?

[Andrew T Wilson (Slow), 2012/08/04 00:54:41]

I do exclude this via chrome_browser.gypi, but all that does is massage the
dependency generation/list of linked files (it doesn't prevent people from
directly #including it). The goal of adding the #if !defined() here is to cause
a compile (not link) error if someone accidentally includes this on cros, with
the expectation that those are easier to diagnose.

If you'd like me to remove this #if or if there's a better idiom to use
(COMPILE_ASSERT?) let me know.

[Mattias Nissler (ping if slow), 2012/08/06 08:33:52]

Ah, that's definitely an interesting idea. Then again, we have lots of code
that's cros-only or non-cros (respectively), and I can't remember having seen
guards like this. Are they common in other parts of the code base?
(Unsignificant) data point: I personally never ran into a situation where I
tried to use something that I shouldn't have been using since it's non-cros or
cros-only.

If we start doing this, we should probably start a concerted effort to convert
over at least all of chrome/browser/policy to this style.
I'd remove it for consistency for now, unless you can point me at precedents in
the code base where this is commonly used.

[Andrew T Wilson (Slow), 2012/08/06 20:30:23]

OK, removed.

+class UserPolicySigninService
+    : public ProfileKeyedService,
+      public OAuth2AccessTokenConsumer,
+      public content::NotificationObserver {
+ public:
+  // Creates a UserPolicySigninService associated with the passed |profile|.
+  UserPolicySigninService(Profile* profile, UserCloudPolicyManager* manager);
+  virtual ~UserPolicySigninService();
+
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  // OAuth2AccessTokenConsumer implementation.
+  virtual void OnGetTokenSuccess(const std::string& access_token,
+                                 const base::Time& expiration_time) OVERRIDE;
+  virtual void OnGetTokenFailure(const GoogleServiceAuthError& error) OVERRIDE;
+
+ private:
+  // Initializes the UserCloudPolicyManager to reflect the currently-signed-in
+  // user.
+  void ConfigureUserCloudPolicyManager();
+
+  // Fetches an OAuth token to allow the cloud policy service to register with
+  // the cloud policy server.
+  void RegisterCloudPolicyService();
+
+  // Weak pointer to the profile this service is associated with.
+  Profile* profile_;
+
+  content::NotificationRegistrar registrar_;
+  scoped_ptr<OAuth2AccessTokenFetcher> oauth2_access_token_fetcher_;
+
+  // Weak pointer to the UserCloudPolicyManager (allows dependency injection
+  // for tests).
+  UserCloudPolicyManager* manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserPolicySigninService);
+};
+#endif  // !defined(OS_CHROMEOS)
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_POLICY_USER_POLICY_SIGNIN_SERVICE_H_