action is marked as succeeded incorrectly before all dependencies succeed

[Yanyan Hu]

Occasionally, an action (e.g. cluster_resize) action could be marked as succeeded incorrect before all its dependencies (e.g. node_delete action) become completed. In the following example, node_delete_da5c854f is a dependency of cluster_resize_66ec62e1. In this case, action status will be reset to READY again after it was marked as SUCCEEDED.

2015-12-04 03:15:30.689 24637 INFO senlin.engine.event [req-95569dd3-392a-416c-aeef-28e9456b4521 3185798e2259423f84be356ec460dce7 a5c78503cefc406fac23244268a7e3e0 - - -] node_delete_da5c854f[9fa859fc-08a2-426b-b5fa-dadb9734d6cb] NODE_DELETE - START: None
2015-12-04 03:15:30.722 24637 INFO senlin.engine.event [req-95569dd3-392a-416c-aeef-28e9456b4521 3185798e2259423f84be356ec460dce7 a5c78503cefc406fac23244268a7e3e0 - - -] node-66ec62e1-003[da5c854f-fb65-480f-9c30-289a9ac3287f] delete - None: None
2015-12-04 03:15:30.725 24637 INFO senlin.engine.event [req-95569dd3-392a-416c-aeef-28e9456b4521 3185798e2259423f84be356ec460dce7 a5c78503cefc406fac23244268a7e3e0 - - -] cluster_resize_66ec62e1[e33e0291-ebdb-4d3a-83ea-4e4b805d563f] CLUSTER_RESIZE - SUCCEEDED: Cluster resize succeeded.
2015-12-04 03:15:30.780 24637 INFO senlin.engine.event [req-95569dd3-392a-416c-aeef-28e9456b4521 3185798e2259423f84be356ec460dce7 a5c78503cefc406fac23244268a7e3e0 - - -] node_delete_da5c854f[9fa859fc-08a2-426b-b5fa-dadb9734d6cb] NODE_DELETE - SUCCEEDED: Node deleted successfully.

Can't reproduce this error now.