Enable sync for the settings from the Extension Settings API.

chrome/browser/extensions/extension_settings_sync_helper.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_EXTENSIONS_EXTENSION_SETTINGS_SYNC_HELPER_H_
+#define CHROME_BROWSER_EXTENSIONS_EXTENSION_SETTINGS_SYNC_HELPER_H_
+#pragma once
+
+#include "base/values.h"
+#include "chrome/browser/sync/api/sync_data.h"
+#include "chrome/browser/sync/api/sync_change.h"
+
+// Helper for creating SyncData and SyncChanges for extension setting objects.
+class ExtensionSettingsSyncHelper {

[Ben Olmstead, 2011/08/31 17:36:43]

We usually just use a namespace for a collection of functions, not a class full
of statics.

[not at google - send to devlin, 2011/09/02 05:00:40]

Done.

Also renamed helper -> util since that seems more common in chromium.

+ public:
+  // Creates a SyncData object for an extension setting.
+  static SyncData CreateData(
+      const std::string& extension_id,
+      const std::string& key,
+      const Value& value);
+
+  // Creates an "add" sync change for an extension setting.
+  static SyncChange CreateAdd(
+      const std::string& extension_id,
+      const std::string& key,
+      const Value& value);
+
+  // Creates an "update" sync change for an extension setting.
+  static SyncChange CreateUpdate(
+    const std::string& extension_id,
+    const std::string& key,
+    const Value& value);
+
+  // Creates a "delete" sync change for an extension setting.
+  static SyncChange CreateDelete(
+      const std::string& extension_id, const std::string& key);
+
+ private:
+  ExtensionSettingsSyncHelper();
+  DISALLOW_COPY_AND_ASSIGN(ExtensionSettingsSyncHelper);
+};
+
+#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_SETTINGS_SYNC_HELPER_H_