[Sync] Move network-related code from core/ to engine/net/.

components/sync/core/http_post_provider_factory.h

-// Copyright 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 COMPONENTS_SYNC_CORE_HTTP_POST_PROVIDER_FACTORY_H_
-#define COMPONENTS_SYNC_CORE_HTTP_POST_PROVIDER_FACTORY_H_
-
-#include <string>
-
-#include "base/callback.h"
-
-namespace net {
-class URLFetcher;
-}
-
-namespace syncer {
-
-typedef base::Callback<void(net::URLFetcher*)> BindToTrackerCallback;
-
-class HttpPostProviderInterface;
-
-// A factory to create HttpPostProviders to hide details about the
-// implementations and dependencies.
-// A factory instance itself should be owned by whomever uses it to create
-// HttpPostProviders.
-class HttpPostProviderFactory {
- public:
-  virtual ~HttpPostProviderFactory() {}
-
-  virtual void Init(const std::string& user_agent,
-                    const BindToTrackerCallback& bind_to_tracker_callback) = 0;
-
-  // Obtain a new HttpPostProviderInterface instance, owned by caller.
-  virtual HttpPostProviderInterface* Create() = 0;
-
-  // When the interface is no longer needed (ready to be cleaned up), clients
-  // must call Destroy().
-  // This allows actual HttpPostProvider subclass implementations to be
-  // reference counted, which is useful if a particular implementation uses
-  // multiple threads to serve network requests.
-  virtual void Destroy(HttpPostProviderInterface* http) = 0;
-};
-
-}  // namespace syncer
-
-#endif  // COMPONENTS_SYNC_CORE_HTTP_POST_PROVIDER_FACTORY_H_