[sync] Componentize sync: Part Final: Target 'sync' is now its own component

sync/syncable/syncable_write_transaction.h

Index: sync/syncable/syncable_write_transaction.h
diff --git a/sync/syncable/syncable_write_transaction.h b/sync/syncable/syncable_write_transaction.h
index ea52d45619d35f3c256d7ed0fef7089104ad3355..8c2cc1fc0e22016f29d7b14098fba2eed190bbc8 100644
--- a/sync/syncable/syncable_write_transaction.h
+++ b/sync/syncable/syncable_write_transaction.h
@@ -5,6 +5,7 @@
 #ifndef SYNC_SYNCABLE_SYNCABLE_WRITE_TRANSACTION_H_
 #define SYNC_SYNCABLE_SYNCABLE_WRITE_TRANSACTION_H_
 
+#include "base/compiler_specific.h"
 #include "sync/base/sync_export.h"
 #include "sync/syncable/entry_kernel.h"
 #include "sync/syncable/syncable_base_transaction.h"
@@ -15,7 +16,8 @@ namespace syncable {
 SYNC_EXPORT extern const int64 kInvalidTransactionVersion;
 
 // Locks db in constructor, unlocks in destructor.
-class SYNC_EXPORT_PRIVATE WriteTransaction : public BaseTransaction {
+class SYNC_EXPORT_PRIVATE WriteTransaction
+    : public NON_EXPORTED_BASE(BaseTransaction) {
  public:
   WriteTransaction(const tracked_objects::Location& from_here,
                    WriterTag writer, Directory* directory);