Decouple HeadsUpManager and ScrollContainer from remote input classes

This cl removes the dependency to the status bar related classes from
the remote input classes (RemoteInputController and RemoteInputView),
so that we can reuse the remote input code from statusbar-less Android
environment like ARC.

Bug: 63874929
Bug: 62602530
Test: Compiled and ran
Change-Id: Id594446592dd9b74ff8ef844ce8eace301b22b56