Clean up language in forced foreground service notifications.

Old:  [ IC ] %s running
      [ ON ] %s is running

New:  [ IC ] %s is running
      [ ON ] Touch for more information or to stop the app.

Additionally, disallow these misbehaving services from
supplying their own content views; if you attempt to run a
foreground service with icon == 0, this is the notification
you will get, period.

Bug: 8525548
Change-Id: I2bfd7340396ef925885e8c2160a720f9eff07a35