注释中的小提琴两件事

(1)循环中的语法无效
数组

(1) the syntax in the loop is invalid
nothing is being done with the array

for (var i = 0; i < 2; i++){
  [ 'Washington', new Date(), new Date() ],  // <-- ??
}

需要使用addRow之类的

for (var i = 0; i < 2; i++){
  dataTable.addRow([ 'Washington', new Date(), new Date() ]);
}

(2)可能是一个错误，但是如果所有行的开始日期和结束日期都相等，
图表将引发错误

(2) it may be a bug but if all the rows have equal start and end dates,
the chart will throw an error

  // dates have close if not equal times
  dataTable.addRow([ 'Washington', new Date(), new Date() ]);

请参阅以下工作片段，
添加了addRow并修改了开始日期...

see following working snippet,
added addRow and modified start date...

google.charts.load('current', {
  callback: drawChart,
  packages: ['timeline']
});

function drawChart() {
  var container = document.getElementById('timeline');
  var chart = new google.visualization.Timeline(container);
  var dataTable = new google.visualization.DataTable();

  dataTable.addColumn({ type: 'string', id: 'President' });
  dataTable.addColumn({ type: 'date', id: 'Start' });
  dataTable.addColumn({ type: 'date', id: 'End' });

  for (var i = 0; i < 2; i++) {
    dataTable.addRow([
      'row ' + (i + 1),
      new Date((new Date()).getTime() - ((i + 1) * 24 * 60 * 60 * 1000)),
      new Date()
    ]);
  }

  chart.draw(dataTable);
}

<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
<div id="timeline" style="height: 180px;"></div>
   

编辑
这是一个使用类似数据的工作示例...

EDIT
here is a working example using similar data...

google.charts.load('current', {
  callback: drawChart,
  packages: ['timeline']
});

function drawChart() {
  var jsonData = [{
    "lineId": 1,
    "lineName": "Line 1",
    "status": 1,
    "dateStart": "2017-08-03T15:10:20.42",
    "dateEnd": "2017-08-03T15:10:23.353"
  }, {
    "lineId": 2,
    "lineName": "Line 2",
    "status": 2,
    "dateStart": "2017-08-03T15:10:30.42",
    "dateEnd": "2017-08-03T15:10:33.353"
  }, {
    "lineId": 3,
    "lineName": "Line 3",
    "status": 3,
    "dateStart": "2017-08-03T15:10:40.42",
    "dateEnd": "2017-08-03T15:10:43.353"
  }, {
    "lineId": 4,
    "lineName": "Line 4",
    "status": 4,
    "dateStart": "2017-08-03T15:10:50.42",
    "dateEnd": "2017-08-03T15:10:53.353"
  }];
  var container = document.getElementById('chart');
  var chart = new google.visualization.Timeline(container);
  var dataTable = new google.visualization.DataTable();

  dataTable.addColumn({type: 'string', id: 'row'});
  dataTable.addColumn({type: 'string', id: 'bar'});
  dataTable.addColumn({type: 'date', id: 'start'});
  dataTable.addColumn({type: 'date', id: 'end'});

  for (var i = 0; i < jsonData.length; i++) {
    dataTable.addRow(
      [jsonData[i].lineName.toString(), jsonData[i].status.toString(), new Date(jsonData[i].dateStart), new Date(jsonData[i].dateEnd)]
    );
  }

  chart.draw(dataTable);
}

<script src="https://www.gstatic.com/charts/loader.js"></script>
<div id="chart"></div>