Recorder: Improve result UI

* Instead of implicit behavior, make it explicit:
  Ask the user after stopping a recording what he wants to do:
  * Confirm: Use the current recording
  * Discard: Delete the recording, return to app that requested
             RECORD_SOUND_ACTION without an Uri
  * Record again: Keep recording but don't use it, instead let the
                  user record again

Co-authored-by: Michael W <baddaemon87@gmail.com>
Change-Id: I47cb581ba99b3e5958f5385e6158c8240b9f86f7