Edit:
This was a bug in Android that was fixed in later versions of Marshmallow
Original:
I believe that this is Marshmallow specific. Are you using a Marshmallow device?
I’ve noticed this error is printed out every time I switch between applications (doesn’t matter which) or exit out of them, and when activities are destroyed.
I’ve tried running the same apps on two Nexus 5s – one running Lollipop and the other Marshmallow, and these log prints only appeared on the Marshmallow version – with every app, not just the one I’m building.
Not sure why this happens, but I opened a report here.