[Sync] Stop deleting LevelDB files when deleting Directory

components/sync/syncable/directory.h

Index: components/sync/syncable/directory.h
diff --git a/components/sync/syncable/directory.h b/components/sync/syncable/directory.h
index d3bd42938b6362149a7ecc5ff1acb7e163a5ebfc..c50407881e0e2370d02033cd27df63875b1b552c 100644
--- a/components/sync/syncable/directory.h
+++ b/components/sync/syncable/directory.h
@@ -527,6 +527,12 @@ class Directory {
   Kernel* kernel();
   const Kernel* kernel() const;
 
+  // Delete the directory database files from the sync data folder to cleanup
+  // backend data. This should happen the first time sync is enabled for a user,
+  // to prevent accidentally reusing old sync data, as well as shutdown when the
+  // user is no longer syncing.
+  static void DeleteDirectoryFiles(const base::FilePath& directory_path);
+
  private:
   friend class SyncableDirectoryTest;
   friend class syncer::TestUserShare;