Release remove inline suggestion views when session destroyed

* Attach to each inline suggestion remote view the user id
  and session id, which together identify a session. Then when
  the session is destroyed, we release all the remote views
  associated with the it.
* Worst scenario is that the IME is still showing the UI when
  the remote view is released due to session destroy, in which
  case the suggestion will disappear from the IME window. But
  we also make sure we send an empty response to IME before
  releasing the views, so it should be bad. Plus when a session
  is destroyed, interacting with the suggestion UI doesn't do
  anything, so it's not very helpful to show them.
* Also add a dump method to the InlineSuggestionRenderService
  to help with debugging

Test: atest android.autofillservice.cts.inline
Bug: 154683107

Change-Id: I488fd9d9af08d0df3ffd3c851f96c567d07eed5a