Add ManagedUserSharedSettingsService.

chrome/browser/managed_mode/managed_user_shared_settings_update.h

+// Copyright 2013 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_MANAGED_MODE_MANAGED_USER_SHARED_SETTINGS_UPDATE_H_
+#define CHROME_BROWSER_MANAGED_MODE_MANAGED_USER_SHARED_SETTINGS_UPDATE_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/callback_list.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace base {
+class Value;
+}
+
+class ManagedUserSharedSettingsService;
+
+// Lets clients of ManagedUserSharedSettingsService change settings and wait for
+// the Sync server to acknowledge the change. The callback passed in the
+// constructor will be called with a true success value when the Sync server
+// flipped the acknowledgement flag for the setting. If another client changes

[Pam (message me for reviews), 2014/01/08 10:30:40]

flips

[Bernhard Bauer, 2014/01/08 11:42:04]

Well, technically it happens a little bit afterwards :) I clarified the comment.

+// the value in the mean time, the callback will be run with a false success
+// value. If the object is destroyed before that, the callback will not be run.
+// Note that any changes made to the setting will not be undone when destroying
+// the object, even if the update was not successful or was canceled.
+class ManagedUserSharedSettingsUpdate {
+ public:
+  ManagedUserSharedSettingsUpdate(
+      ManagedUserSharedSettingsService* service,
+      const std::string& mu_id,
+      const std::string& key,
+      scoped_ptr<base::Value> value,
+      const base::Callback<void(bool)>& success_callback);
+  ~ManagedUserSharedSettingsUpdate();
+
+ private:
+  typedef base::CallbackList<void(const std::string&, const std::string&)>
+      CallbackList;
+
+  void OnSettingChanged(const std::string& mu_id,
+                        const std::string& key);
+
+  ManagedUserSharedSettingsService* service_;
+  std::string mu_id_;
+  std::string key_;
+  scoped_ptr<base::Value> value_;
+  base::Callback<void(bool)> callback_;
+  scoped_ptr<CallbackList::Subscription> subscription_;
+};
+
+#endif  // CHROME_BROWSER_MANAGED_MODE_MANAGED_USER_SHARED_SETTINGS_UPDATE_H_