I have observed that "Generate ChangeEntries" is by default checked in the 11.x for the custom Rowsource whereas in 4.x it was not.
If anyone knows any specific advantage for the same please do let me know.
if you are going to map the custom row source to any cube then set it to true otherwise false.
Generally we map it to cube so it is by default set to true in 11.x. Change list entries will be generated if you set it to true.