[Sync] Convert sync to a static library.

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/base/sync_export.h"
 #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 SYNC_EXPORT UserShare {
+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_