@Override
    protected void onBlur() {
        TableCellElement td = getKeyboardSelectedTableCellElement();
        if (td != null) {
            TableRowElement tr = td.getParentElement().cast();
            td.removeClassName(style.keyboardSelectedCell());
            setRowStyleName(tr, style.keyboardSelectedRow(), style.keyboardSelectedRowCell(), false);
        }
    }
Get the thead element that contains the headers.
stroom-core-client-widget/src/main/java/com/google/gwt/user/cellview/client/AbstractCellTable.java