This is dead code, it is here for convenience for those testing current devel so as to ascertain if a bug was introduced in the v2 rewrite or was preexisting in the 1.x codebase.
Using this code should be equivalent of checking out the v1_last tag, which was devel at a point between 1.9.1 and 1.9.2 releases.
The stable-1.9 is the maintenance branch for the 1.9.x code, which might continue to diverge from the v1/ tree as bugs get fixed.

DO NOT:
 * use this code as reference
 * make PRs against this code
 * expect this code to be shipped with the 2.0 version of ansible


