We previously didn't allow home activities to be resizeable due to not fully
understanding how the UX would work. We now have a better idea of how the UX will
work. However, since this is a behavior change for home activities we require them
to explicitly say they want to be resizeable vs. the framework assuming they can
be resizeable based on their target sdk.
Bug: 30982291
Test: cts/hostsidetests/services/activityandwindowmanager/util/run-test android.server.cts
Change-Id: I41aefc8c3b3da4c2cf66be81835222196df3ef26
df241e9771