Remove `ShadowActivity#onCreate`

Was investigating issue #677 and noticed that the `FragmentManager` was not getting properly initialized. Traced it back to the `ShadowActivity` overriding `onCreate` to be a no-op. `onCreate` is where the `Activity` normally initializes the `FragmentManager`.

Then fixed the `recreateGoesThroughFullLifeCycle` test to use the `ActivityController` because `recreate` no longer worked with an unattached `Activity`.

Now `Activity` layouts can contain `<fragment>` tags without using the support library :smile: