$('.ke-edit-iframe').contents().find('body').text()

<iframe class="ke-edit-iframe" hidefocus="true" frameborder="0" style="width: 100%; height: 144px;"></iframe>

<div style="display: block; height: 144px;" class="ke-edit"><iframe class="ke-edit-iframe" hidefocus="true" frameborder="0" style="width: 100%; height: 144px;"></iframe><textarea class="ke-edit-textarea" hidefocus="true" style="width: 100%; height: 144px; display: none;"></textarea></div>