/**
  * Persists this folder. We will always perform the proper database operation (e.g. 'save' or
  * 'update'). As an optimization, if a folder has not been modified, no database operations are
  * performed.
  */
 void save(Context context) {
   final Mailbox mailbox = mMailbox;
   if (!mailbox.isSaved()) {
     mailbox.save(context);
     mHash = mailbox.getHashes();
   } else {
     Object[] hash = mailbox.getHashes();
     if (!Arrays.equals(mHash, hash)) {
       mailbox.update(context, mailbox.toContentValues());
       mHash = hash; // Save updated hash
     }
   }
 }