Description of problem:

OSP10 -> OSP13 FFU upgrade: upgrade_steps_playbook.yaml fails: The error was: error while evaluating conditional ((httpd_enabled.rc == 0) and (httpd_running.rc == 0) and (step|int == 2)): 'httpd_enabled' is undefined

The problems is caused by the upgrade tasks with 'common' tags are rendered _after_ the tasks which use conditions including variables registered by the 'common' tasks.

In this particular case the failure shows:

TASK [Stop and disable aodh service (running under httpd)] ************************************************************************************************************************************************************************************
fatal: [192.168.24.9]: FAILED! => {"failed": true, "msg": "The conditional check '(httpd_enabled.rc == 0) and (httpd_running.rc == 0) and (step|int == 2)' failed. The error was: error while evaluating conditional ((httpd_enabled.rc == 0) and (httpd_running.rc == 0) and (step|int == 2)): 'httpd_enabled' is undefined\n\nThe error appears to have been in '/home/stack/tripleo-40rIhX-config/Controller/upgrade_tasks.yaml': line 1, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n- name: Stop and disable aodh service (running under httpd)\n ^ here\n"}

We can see the content of the playbook here: http://paste.openstack.org/show/646497/

The first task( Stop and disable aodh service (running under httpd)) has the following condition:
when: (httpd_enabled.rc == 0) and (httpd_running.rc == 0) and (step|int == 2)

Nor httpd_enabled or are httpd_running defined at this point. They are defined at line 496 and line 501 respectively.

We need to run the tasks with 'common' tags before the reset of the tasks so the vars registered in 'common' tasks are available.