code: function(event, element, elementType) {
  
  			if (elementType === 'todo-label') {
  				var todoEl = getClosestTodoElement(element);
  
  				event.preventDefault();
  				event.stopPropagation();
  
  				this.showEditor(todoEl);
  			}
  
  		}
docs: Handles double click 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}