This resulted in a notable increase to the size of the basic material app binary.

My understanding is that our current internal customers are all using the Android support libraries because they are required for Google login, and probably a lot of our external customers will want to use Google API auto-management in their app, or inherit from FragmentActivity for some reason.

There's not an easy way to have FlutterActivity extend FragmentActivity on some apps and Activity on others, but I guess we could provide a FlutterFragmentActivity if we really wanted to punt this choice to the developers and give them the option to shave 500kb off their APK size.

I think we should re-baseline the benchmark, but I'm open to feedback / other approaches.

/cc @abarth