Dispatch hover events through the input consumer proxy

- Touch explore uses hover events to focus views for accessibility, but
  we were dropping these events when handling them through the input
  consumer proxy.  The reason this changed is that in sc-v2 we moved the
  recents input consumer to the top of the task display area to ensure
  that it was always above any of the tasks in splitscreen, but by doing
  so, it was always above launcher even after settling in overview.  The
  existing path for handling motion events is heavily tied to touch
  handling (action down/move/up) so we just add a separate path for
  dispatching hover events through the normal mechanism to launcher via
  the consumer.

Bug: 197043796
Change-Id: I5f8cfd357ff13971fe172ce1d0179535479cd26c