[Ravenwood] Move *_host classes into their corresponding package

This allows the host classes to reference package private members of the
original class. This also makes the redirection class annotation much
cleaner, as the host classes are in the same package.

Bug: 292141694
Flag: EXEMPT host test change only
Test: $ANDROID_BUILD_TOP/frameworks/base/ravenwood/scripts/run-ravenwood-tests.sh
Change-Id: I01c184ddc3c8cf5d075113e310296c67e0b697d1