title: Kendo UI - js grid destroy function not triggered
body: <p>This is my grid: </p>
  
  <pre><code>  $(document).ready(function () {
  datasource = new kendo.data.DataSource({
      transport: {
          read: {
              url: '/Discount/Get',
              dataType: "json",
          },
          update: {
              url: '/Discount/Update',
              dataType: "json",
              type: "POST"
          },
          destroy: {
              url: '/Discount/Delete',
              dataType: "json",
              type: "POST"
          },
          create: {
              url: '/Discount/Add',
              dataType: "json",
              type: "POST"
          },
          parameterMap: function (options, operation) {
              console.log(operation);
              if (operation !== "read") {
                  return options;
              }
          }
      },
      schema: {
          model: {
              id: "Id",
              fields: {
                  TopItemName: { type: "string" },
                  DiscountValue: { type: "number" },
              }
          }
      }
  });
  $("#grid").kendoGrid({
      dataSource: datasource,
      batch: true,
      toolbar: ["create", "save", "cancel"],
      height: 400,
      navigatable: true,
      pageable: true,
      columns: [
      {
          field: "TopItemName",
          editor: topItemDropDown,
          template: "#=TopItemName#"
      },
      {
          field: "DiscountValue",
          format: "{0:p0}",
          editor: function (container, options) {
              $("&lt;input name='DiscountValue'&gt;")
              .appendTo(container)
              .kendoNumericTextBox(
                {
                    min: 0,
                    max: 1.00,
                    step: 0.01
                });
          }
      },
      {
          command: "destroy",
          title: "&amp;nbsp;",
          width: 150
      }],
      editable: true
  });
  
  function topItemDropDown(container, options) {
      console.log(options);
      $('&lt;input required data-text-field="TopItemName" data-value-field="TopItemName" data-bind="value:' + options.field + '"/&gt;')
          .appendTo(container)
          .kendoDropDownList({
              autoBind: false,
              dataSource: {
                  serverFiltering: true,
                  transport: {
                      read: {
                          url: '/Discount/GetTopItemName',
                          dataType: "json",
                          type: "POST",
                          contentType: "application/json"
                      }
                  }
              }
          });
      }
  </code></pre>
  
  <p>});</p>
  
  <p>and somehow when I press the delete button it deletes the row from the grid but it never calls my action method so that the row gets removed from my database. But if I after i have pressed the delete button press add new record and then save changes then it calls my add action method and my delete action method. How can I make it call the delete action method when the delete button is pressed and not when save changes is pressed?</p>