Android本地备份功能禁用

最近部分设备激活客户端后发现本地备份的功能被禁用了，排查原因发现：

 /**
     * Allows the device owner to enable or disable the backup service.
     *
     * <p> Backup service manages all backup and restore mechanisms on the device. Setting this to
     * false will prevent data from being backed up or restored.
     *
     * <p> Backup service is off by default when device owner is present.
     *
     * @param admin Which {@link DeviceAdminReceiver} this request is associated with.
     * @param enabled {@code true} to enable the backup service, {@code false} to disable it.
     * @throws SecurityException if {@code admin} is not a device owner.
     */
    public void setBackupServiceEnabled(@NonNull ComponentName admin, boolean enabled) {
        throwIfParentInstance("setBackupServiceEnabled");
        try {
            mService.setBackupServiceEnabled(admin, enabled);
        } catch (RemoteException re) {
            throw re.rethrowFromSystemServer();
        }
    }

客户端设置了deviceOwner后，备份会默认关闭，所以需要调用该方法设置为true.