The first one is better.
It’s more consistent with other event functions in the Activity API, it costs you nothing (the code you’re calling does nothing at the moment), and it means you don’t need to remember to add the call in the future when the behaviour of the base class changes.
Edit
As Su-Au Hwang has pointed out, my prediction about the behaviour of the base class changing in the future has come true! FragmentActivity requires you to call the method on super.