[Sync] Convert sync to a static library.

components/sync/syncable/syncable_model_neutral_write_transaction.h

 // Copyright 2013 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_SYNCABLE_SYNCABLE_MODEL_NEUTRAL_WRITE_TRANSACTION_H_
 #define COMPONENTS_SYNC_SYNCABLE_SYNCABLE_MODEL_NEUTRAL_WRITE_TRANSACTION_H_
 
 #include "base/macros.h"
-#include "components/sync/base/sync_export.h"
 #include "components/sync/syncable/metahandle_set.h"
 #include "components/sync/syncable/syncable_base_write_transaction.h"
 
 namespace syncer {
 namespace syncable {
 
 // A transaction used to instantiate Entries or ModelNeutralMutableEntries.
 //
 // This allows it to be used when making changes to sync entity properties that
 // do not need to be kept in sync with the associated native model.
 //
 // This class differs internally from WriteTransactions in that it does a less
 // good job of tracking and reporting on changes to the entries modified within
 // its scope.  This is because its changes do not need to be reported to the
 // DirectoryChangeDelegate.
-class SYNC_EXPORT ModelNeutralWriteTransaction : public BaseWriteTransaction {
+class ModelNeutralWriteTransaction : public BaseWriteTransaction {
  public:
   ModelNeutralWriteTransaction(const tracked_objects::Location& location,
                                WriterTag writer,
                                Directory* directory);
   ~ModelNeutralWriteTransaction() override;
 
   void TrackChangesTo(const EntryKernel* entry) override;
 
  private:
   MetahandleSet modified_handles_;
 
   DISALLOW_COPY_AND_ASSIGN(ModelNeutralWriteTransaction);
 };
 
 }  // namespace syncable
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_SYNCABLE_SYNCABLE_MODEL_NEUTRAL_WRITE_TRANSACTION_H_