Re-render grid when expanding group

[rajdsouza]

In slick.groupitemmetadataprovider.js

add this.resizeCanvas() as it helps to re-render the grid when a grid is initiated in collapse mode

function handleGridClick(e, args) {
      var item = this.getDataItem(args.row);
      if (item && item instanceof Slick.Group && $(e.target).hasClass(options.toggleCssClass)) {
        var range = _grid.getRenderedRange();
        this.getData().setRefreshHints({
          ignoreDiffsBefore: range.top,
          ignoreDiffsAfter: range.bottom + 1
        }); //take diff till range.bottom , and ignore it after.

        if (item.collapsed) {
          this.getData().expandGroup(item.groupingKey);
        } else {
          this.getData().collapseGroup(item.groupingKey);
        }
        this.resizeCanvas();
        e.stopImmediatePropagation();
        e.preventDefault();
      }
    }