title: jqGrid is empty, even though pager shows results
body: <p>I'm upgrading from jqGrid 3.6.3 -> 4.1.2.</p>
  
  <p>After upgrading the grid always displays empty, even though the pager shows the correct number of results (6 in this case). I can see that the JSON is being retrieved and is valid.</p>
  
  <p>No error is displayed, and nothing is written to the javascript console.
  If I hook into the loadComplete event, it fires -- and grid.getDataIDs() returns an empty array - as if there were no data.</p>
  
  <p>Here is the JSON being transmitted (formatted with JSONLint). It is properly formatted JSON &amp; passes JSONLint validation:</p>
  
  <pre><code>{
      "pageCount": "1",
      "pageSize": "15",
      "pageNumber": "1",
      "itemCount": "6",
      "items": [
          {
              "Id": "1",
              "Name": "Administrator"
          },
          {
              "Id": "3",
              "Name": "asfasfassf"
          },
          {
              "Id": "6",
              "Name": "askjdhajksdk sh"
          },
          {
              "Id": "2",
              "Name": "fg"
          },
          {
              "Id": "5",
              "Name": "test"
          },
          {
              "Id": "4",
              "Name": "sa afasf saf"
          }
      ]
  }
  </code></pre>
  
  <p>Here is the relevant portion of the jqGrid options that I am passing into jqGrid:</p>
  
  <pre><code>{
      datatype: 'json',
      jsonReader: {
          root: 'items',
          id: '0',
          repeatitems: false,
          page: 'pageNumber',
          total: 'pageCount',
          records: 'itemCount'
      },
      mtype: 'POST',
      ...
  };
  </code></pre>
  
  <p>I have scoured the interwebs for an answer, but no luck. Does anyone have a suggestion?!</p>
  
  <p>See below a screenshot of the options object that I am passing into jqGrid(options):</p>
  
  <p><img src="https://i.stack.imgur.com/ZL4Yi.png" alt="jqgrid options object"></p>
  
  <p>Thanks in advance!!!</p>