Enable sync for the settings from the Extension Settings API.

chrome/browser/extensions/extension_settings_api.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_API_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_SETTINGS_API_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "chrome/browser/extensions/extension_function.h"
 #include "chrome/browser/extensions/extension_settings.h"
 #include "chrome/browser/extensions/extension_settings_storage.h"
+#include "chrome/browser/extensions/syncable_extension_settings_storage.h"
 
 // Superclass of all settings functions.
 class SettingsFunction : public AsyncExtensionFunction {
  public:
   // Extension settings function implementations should do their work here, and
   // either run a StorageResultCallback or fill the function result / call
   // SendResponse themselves.
   // The exception is that implementations can return false to immediately
   // call SendResponse(false), for compliance with EXTENSION_FUNCTION_VALIDATE.
   virtual bool RunWithStorageImpl(ExtensionSettingsStorage* storage) = 0;
@@ skipping 10 matching lines @@
     virtual ~StorageResultCallback();
     virtual void OnSuccess(DictionaryValue* settings) OVERRIDE;
     virtual void OnFailure(const std::string& message) OVERRIDE;
 
    private:
     scoped_refptr<SettingsFunction> settings_function_;
   };
 
  private:
   // Callback method from GetStorage(); delegates to RunWithStorageImpl.
-  void RunWithStorage(ExtensionSettingsStorage* storage);
+  void RunWithStorage(SyncableExtensionSettingsStorage* storage);
 };
 
 class GetSettingsFunction : public SettingsFunction {
  public:
   DECLARE_EXTENSION_FUNCTION_NAME("experimental.settings.get");
 
  protected:
   virtual bool RunWithStorageImpl(ExtensionSettingsStorage* storage) OVERRIDE;
 };
 
@@ skipping 15 matching lines @@
 
 class ClearSettingsFunction : public SettingsFunction {
  public:
   DECLARE_EXTENSION_FUNCTION_NAME("experimental.settings.clear");
 
  protected:
   virtual bool RunWithStorageImpl(ExtensionSettingsStorage* storage) OVERRIDE;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_SETTINGS_API_H_