$ sudo apt-get update
$ sudo apt-get install lxsession-data 

lxsession-data is installed in your system.

Make ensure the lxsession-data package were installed using the commands given below,

$ sudo dpkg-query -l | grep lxsession-data *

You will get with lxsession-data package name, version, architecture and description in a table

lxsession-data package basic information: