[Sync] Move some directory-related things from core/ to syncable/.

components/sync/core/user_share.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_USER_SHARE_H_
-#define COMPONENTS_SYNC_CORE_USER_SHARE_H_
-
-#include <memory>
-#include <string>
-
-#include "components/sync/core/sync_manager.h"
-
-namespace syncer {
-
-namespace syncable {
-class Directory;
-}
-
-// A UserShare encapsulates the syncable pieces that represent an authenticated
-// user and their data (share).
-// This encompasses all pieces required to build transaction objects on the
-// syncable share.
-struct UserShare {
-  UserShare();
-  ~UserShare();
-
-  // The Directory itself, which is the parent of Transactions.
-  std::unique_ptr<syncable::Directory> directory;
-
-  // The credentials used by sync when talking to the sync server.
-  //
-  // Note: some or all of the sync_credentials fields may be empty.
-  SyncCredentials sync_credentials;
-};
-
-}  // namespace syncer
-
-#endif  // COMPONENTS_SYNC_CORE_USER_SHARE_H_