Previously, we were filtering the task list on tags for each host
that was including the file, based on the idea that the variables
had to include the host information. However, the top level task
filtering is play-context only, which should also apply to the
included tasks. Tags cannot and should not be based on hostvars.
* Properly mark hosts with failures in includes as failed
* Don't send callbacks until we're sure we're done, and also fix how
we increment stats so failures don't show up as ok's
* Fix a bug in the include file logic where a failed include could lead
to an infinite loop in the task iteration logic
Fixes#12933