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##### SUMMARY
include_role complains if parameter vars_from is given but no vars file exists

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
include_role

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.6
  config file = /adm/afroebel/ansible/unix/ansible.cfg
  configured module search path = [u'/adm/afroebel/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/dist-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.9 (default, Sep 14 2019, 20:00:08) [GCC 4.9.2]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
DEFAULT_GATHERING(/adm/afroebel/ansible/unix/ansible.cfg) = explicit
DEFAULT_MANAGED_STR(/adm/afroebel/ansible/unix/ansible.cfg) = {file}
DEFAULT_PRIVATE_ROLE_VARS(/adm/afroebel/ansible/unix/ansible.cfg) = True
DEFAULT_ROLES_PATH(env: ANSIBLE_ROLES_PATH) = [u'/adm/afroebel/ansible/unix/test']
PERSISTENT_CONNECT_TIMEOUT(/adm/afroebel/ansible/unix/ansible.cfg) = 30
```

##### OS / ENVIRONMENT
Ansible controller: Debian GNU/Linux 8
managed devices: Oracle Solaris 11.3/11.4


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->

Here's a simple Ansible playbook file test/include_role.yml with a single include_role task:
```yaml
---
- name:   "Test Playbook"
  hosts:  "os_solaris"
  tasks:
    - include_role:
        name:      "test_role/solaris"
```
The role consists of the following files and directories and only executes one debug task, which outputs the role name:

```
drwxr-xr-x 4 ... test/roles/test_role/solaris
drwxr-xr-x 2 ... test/roles/test_role/solaris/tasks
-rw-r--r-- 1 ... test/roles/test_role/solaris/tasks/main.yml
drwxr-xr-x 2 ... test/roles/test_role/solaris/vars
```
When executed as follow all works well:

```
# ansible-playbook -i inventory test/include_role.yml -l test07

PLAY [Test Playbook] **************************************************************

TASK [include_role : test_role/solaris] *******************************************

TASK [test_role/solaris : debug] **************************************************
ok: [test07] => {
    "msg": "test_role/solaris"
}

PLAY RECAP ************************************************************************
test07  : ok=1  changed=0  unreachable=0  failed=0  skipped=0  rescued=0  ignored=0
```

Now we slightly change the Playbook by adding the vars_from parameter to the include_role statement and setting it to the default value of "main".
```yaml
---
- name:   "Test Playbook"
  hosts:  "os_solaris"
  tasks:
    - include_role:
        name:      "test_role/solaris"
        vars_from: "main"

```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
As we set the vars_from parameter to the default value we would expect the playbook to run the same way as without the parameter.

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
Instead it complains about the vars file not being found.

<!--- Paste verbatim command output between quotes -->
```paste below
PLAY [Test Playbook] **************************************************************

TASK [include_role : test_role/solaris] *******************************************
ERROR! Could not find specified file in role: vars/main

PLAY RECAP ************************************************************************
```

role_name = include_args.pop('name', include_args.pop('role', None))
                        if role_name is not None:
                            role_name = templar.template(role_name)
                        new_task = original_task.copy()
                        new_task._role_name = role_name
                        for from_arg in new_task.FROM_ARGS:
                            if from_arg in include_args:
                                from_key = from_arg.replace('_from', '')
                                new_task._from_files[from_key] = templar.template(include_args.pop(from_arg))
                        inc_file = IncludedFile(role_name, include_args, special_vars, new_task, is_role=True)
                    idx = 0
                    orig_inc_file = inc_file
                    while 1:
                        try:
                            pos = included_files[idx:].index(orig_inc_file)
                            
                            
                            inc_file = included_files[idx + pos]
                        except ValueError:
                            included_files.append(orig_inc_file)
                            inc_file = orig_inc_file
                        try:
                            inc_file.add_host(original_host)
                        except ValueError:
                            
                            idx += pos + 1
                        else:
                            break
        return included_files