Check for ansible_facts in results for with_ tasks

that loop over a lookup plugin. Fixes #3704 and #3735

Given the playbook
``` yaml
- hosts: localhost
  gather_facts: False
  tasks:
  - set_fact: specialvar={{item}}
    with_items:
    - a
    - b
    - c
    - d
  - debug: msg={{specialvar}}
```
gives:
``` yaml
TASK: [set_fact specialvar={{item}}] ****************************************** 
ok: [localhost] => (item=a)
ok: [localhost] => (item=b)
ok: [localhost] => (item=c)
ok: [localhost] => (item=d)

TASK: [debug msg={{specialvar}}] ********************************************** 
ok: [localhost] => {"msg": "{{specialvar}}"}
```
but with this patch this becomes:
``` yaml
TASK: [set_fact specialvar={{item}}] ****************************************** 
ok: [localhost] => (item=a)
ok: [localhost] => (item=b)
ok: [localhost] => (item=c)
ok: [localhost] => (item=d)

TASK: [debug msg={{specialvar}}] ********************************************** 
ok: [localhost] => {"msg": "d"}
```
Obviously there are more usefull examples (in my case using `with_random_choice`)