If a `menuId` is not provided then it'll return the first menu found.
If a `menuId` is `left` or `right`, then it'll return the enabled menu
on that side. Otherwise, if a `menuId` is provided, then it'll try to
find the menu using the menu's `id` property. If a menu is not found
then it'll return `null`. If a menu id was provided, but was not found,
it will not fallback to finding any menu. Closes#5535
004e63555e