So one of the "problems" with crypto + Android is that Robolectric will include an Activity class when we run our Android tests on the JVM.  

SpongeyCastle won't run on the JVM because it is signed incorrectly (or some other nonsense).  The SC maintainer isn't worried because if you are on the JVM you should be using Bouncy Castle instead anyway.  What this means is that right now the change isn't necessary but in the future it may be beneficial if we choose to let the ANDROID_ACTIVITY_CLASS value be overridden at start up.