Health check result array [null] returned in embedded tasks sometimes

[sttts]

Might be related to #1082.

[sttts]

"tasks": [
            {
                "appId": "/hotel",
                "healthCheckResults": [
                    null
                ],
                "host": "192.168.2.2",
                "id": "hotel.13fa9af6-a607-11e4-b784-9a6f81a7ceff",
                "ports": [
                    32005
                ],
                "stagedAt": "2015-01-27T09:30:05.814Z",
                "startedAt": "2015-01-27T09:30:09.442Z",
                "version": "2015-01-27T09:30:00.709Z"
            }
        ],

[drexin]

Moved to 0.8.1, as this is not critical.

[bobrik]

null resulted in health check that was alive: false in our service discovery. This is probably still related to #1082. alive: false is not bad per se, it's bad because previous task was killed before the new one became healthy.

Transition:

[
  {
    "id": "totally_different_path.361e84d1-b041-11e4-bc81-56847afe9799",
    "host": "web33",
    "ports": [
      31005
    ],
    "startedAt": "2015-02-09T09:52:12.080Z",
    "stagedAt": "2015-02-09T09:51:25.529Z",
    "version": "2015-02-09T09:51:20.692Z",
    "appId": "/totally/different/path"
  }
]

[
  {
    "id": "totally_different_path.361e84d1-b041-11e4-bc81-56847afe9799",
    "host": "web33",
    "ports": [
      31005
    ],
    "startedAt": "2015-02-09T09:52:12.080Z",
    "stagedAt": "2015-02-09T09:51:25.529Z",
    "version": "2015-02-09T09:51:20.692Z",
    "appId": "/totally/different/path",
    "healthCheckResults": [
      null
    ]
  }
]

[
  {
    "id": "totally_different_path.361e84d1-b041-11e4-bc81-56847afe9799",
    "host": "web33",
    "ports": [
      31005
    ],
    "startedAt": "2015-02-09T09:52:12.080Z",
    "stagedAt": "2015-02-09T09:51:25.529Z",
    "version": "2015-02-09T09:51:20.692Z",
    "appId": "/totally/different/path",
    "healthCheckResults": [
      {
        "alive": true,
        "consecutiveFailures": 0,
        "firstSuccess": "2015-02-09T09:54:41.307Z",
        "lastFailure": null,
        "lastSuccess": "2015-02-09T09:54:41.307Z",
        "taskId": "totally_different_path.361e84d1-b041-11e4-bc81-56847afe9799"
      }
    ]
  }
]