Refactor auto-fill

* Fix a layering issue where auto-fill manager which is in view
  depended on activity which is in app

* Moved auto-fill classes to view or service based on their
  purpose and removed dependecy on the classes in view to the
  classes in service

* Push state to local auto-fill manager whether auto-fill is
  enabled to avoid making IPC for every focus transition if
  the user did not enable the feature

* Remove unnecessary offload to messages when handling calls
  to auto-fill manager service as these are made over a oneway
  interface and in general they do almost no work and typically
  we do these on the binder thread

* Removed id from data set and fill response as the provider
  can embed everything it needs to id them in the auth pending
  intent

* Enforce the auth UI to be only an activity as this will work
  with multi-window, recents, and back and also does not require
  draw on top of other app special permission

* Authentication also no longer requires passing a remotable
  callback to the auth activity but the activity handles the
  request as if called for a result

* Handling stopping of a user to clean up in-memory state as
  well as handling when a user gets unlocked as a provider may
  be non-direct boot aware

* User the correct context when creating an auto-fill manager

* Move the receiver that listens for requests to hide system
  windows to the manager service as the UI is a singleton and
  no need every per-user state to register its own

* Removed extras from dataset as the only case a provider needs
  to associate state with a dataset is for auth and the provider
  can embed this data in the auth pending intent

Test: manual and CTS

Change-Id: I4bc54c13cf779d7f6fdb3ab894637f9fac73f603