code: function(event, element, elementType) {
  
  			if (elementType === 'mark-as-complete-checkbox') {
  				var todoEl = getClosestTodoElement(element),
  					todoId = getClosestTodoId(element);
  
  				if (element.checked) {
  					todoEl.classList.add('completed');
  					todosDB.markAsComplete(todoId);
  				} else {
  					todoEl.classList.remove('completed');
  					todosDB.markAsIncomplete(todoId);
  				}
  
  				context.broadcast('todostatuschange');
  
  			}
  
  		}
docs: Handles change events for the behavior.
  @param {Event} event A DOM-normalized event object.
  @param {HTMLElement} element The nearest HTML element with a data-type
  attribute specified or null if there is none.
  @param {string} elementType The value of data-type for the nearest
  element with that attribute specified or null if there is none.
  @returns {void}