[refactor] router: comment out "div" parameter

In the `update()` function, even if the `comp` parameter is undefined, it falls back to "div".
This commit slightly reduces the bundle size and optimizes the component fallback process.

Author: kfule

api/router.js

@@ -104,7 +104,7 @@ module.exports = function($window, mountRedraw) {
 							return payload.onmatch(data.params, path, matchedRoute)
 						}).then(update, path === fallbackRoute ? null : reject)
 					}
-					else update("div")
+					else update(/* "div" */)
 					return
 				}
 			}