I found my answer. I have replaced inline Action Icons(delete and Notes icons) using IcoMoon App (http://icomoon.io/app/). I selected different icons I needed from IcoMoon website and created a stylesheet that I downloaded and added to my application. And using the class name("idoc-icon-trash") provided by IcoMoon I added below code in my afterInsertRow event and boooom.. it worked as shown in the figure.
$("#gridJQ .ui-icon-trash").removeClass('ui-icon ui-icon-trash').addClass('idoc-icon-trash');
.idoc-icon-trash {
font-size: 19px;
color: #022462;
}