mResponse.addAttribute(MailService.A_TOKEN, mbox.getLastChangeID()); if (mBegin <= 0) {
if (mToken <= 0) { mResponse.addAttribute(MailService.A_TOKEN, mbox.getLastChangeID());
    protected void callback() throws ServiceException {        Mailbox mbox = getMailbox();        synchronized (mbox) {            mbox.beginTrackingSync(null);            mResponse.addAttribute(MailService.A_TOKEN, mbox.getLastChangeID());            if (mBegin <= 0) {                mResponse.addAttribute(MailService.A_SIZE, mbox.getSize());                Folder root = null;                try {                    int folderId = (int) mRequest.getAttributeLong(MailService.A_FOLDER, DEFAULT_FOLDER_ID);                    OperationContext octxtOwner = new OperationContext(mbox.getAccount());                    root = mbox.getFolderById(octxtOwner, folderId);                } catch (MailServiceException.NoSuchItemException nsie) { }                Set<Folder> visible = mbox.getVisibleFolders(getOpCtxt());                boolean anyFolders = folderSync(mZsc, mResponse, mbox, root, visible, SyncPhase.INITIAL);                // if no folders are visible, add an empty "<folder/>" as a hint                if (!anyFolders)                    mResponse.addElement(MailService.E_FOLDER);            } else {                deltaSync(mZsc, mResponse, mbox, mBegin, mRequest.getAttributeBool(MailService.A_TYPED_DELETES, false));            }        }    }