code: function returnFocus(hidingParent, previousActiveElement, hideCallback) {
  		var activeElement = document.activeElement;
  		var hasFocus = hidingParent && (hidingParent === activeElement || (hidingParent.compareDocumentPosition(activeElement) & 16) !== 0);
  		if (hideCallback) {
  			hideCallback();
  		}
  		var temp = previousActiveElement;
  		if (hasFocus) {
  			while (temp && temp !== document.body) {
  				if (document.compareDocumentPosition(temp) !== 1 && temp.offsetParent) {
  					var tabbable = firstTabbable(temp, previousActiveElement === temp);
  					if (tabbable) {
  						temp = tabbable;
  						break;
  					}
  				}
  				if (temp.classList.contains("contextMenu")) {
  					if (temp.triggerNode) {
  						temp = temp.triggerNode;
  						continue;
  					}
  					break;
  				}
  				temp = temp.parentNode;
  			}
  			if (temp) {
  				temp.focus();
  				return true;
  			}
  		}
  		return false;
  	}
docs: Return focus to the element that was active before the <code>hidingParent</code> was
  shown if the parent contains the active element. If the previous active node is no
  longer available, the first tabbable in the nearest ancestor is focused.
  
  @name orion.webui.littlelib.returnFocus
  @function
  @static
  @param {Element} hidingParent The node that is hiding
  @param {Element} previousActiveElement The previously focus node