code: function findFocusableDomRef(oContainer, bForward) {
  
  		var oChild = bForward ? oContainer.firstChild : oContainer.lastChild,
  			oFocusableDescendant;
  
  		while (oChild) {
  
  			if ( oChild.nodeType == 1 && !isHidden(oChild) ) {
  
  				if ( jQuery(oChild).hasTabIndex() ) {
  					return oChild;
  				}
  
  				oFocusableDescendant = findFocusableDomRef(oChild, bForward);
  				if (oFocusableDescendant) {
  					return oFocusableDescendant;
  				}
  
  			}
  
  			oChild = bForward ? oChild.nextSibling : oChild.previousSibling;
  
  		}
  
  		return null;
  	}
docs: Searches for a descendant of the given node that is an Element and focusable and visible.
  
  The search is executed 'depth first'.
  
  @param {Node} oContainer Node to search for a focusable descendant
  @param {boolean} bForward Whether to search forward (true) or backwards (false)
  @returns {Element} Element node that is focusable and visible or null
  @private