Move most of the component updater artifacts to update_client.

components/component_updater/update_checker.h

-// Copyright 2014 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 COMPONENTS_COMPONENT_UPDATER_UPDATE_CHECKER_H_
-#define COMPONENTS_COMPONENT_UPDATER_UPDATE_CHECKER_H_
-
-#include <string>
-#include <vector>
-
-#include "base/callback.h"
-#include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
-#include "components/component_updater/update_response.h"
-#include "url/gurl.h"
-
-class GURL;
-
-namespace net {
-class URLRequestContextGetter;
-}
-
-namespace component_updater {
-
-class Configurator;
-struct CrxUpdateItem;
-
-class UpdateChecker {
- public:
-  typedef base::Callback<void(const GURL& original_url,
-                              int error,
-                              const std::string& error_message,
-                              const UpdateResponse::Results& results)>
-      UpdateCheckCallback;
-
-  virtual ~UpdateChecker() {}
-
-  // Initiates an update check for the |items_to_check|. |additional_attributes|
-  // provides a way to customize the <request> element. This value is inserted
-  // as-is, therefore it must be well-formed as an XML attribute string.
-  virtual bool CheckForUpdates(
-      const std::vector<CrxUpdateItem*>& items_to_check,
-      const std::string& additional_attributes,
-      const UpdateCheckCallback& update_check_callback) = 0;
-
-  static scoped_ptr<UpdateChecker> Create(const Configurator& config);
-
- protected:
-  UpdateChecker() {}
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(UpdateChecker);
-};
-
-}  // namespace component_updater
-
-#endif  // COMPONENTS_COMPONENT_UPDATER_UPDATE_CHECKER_H_