`class type intersectionObserverEntry = object ... end`
`class type intersectionObserverOptions = object ... end`
`class type intersectionObserver = object ... end`
`val empty_intersection_observer_options : unit -> intersectionObserverOptions Js.t`
`val is_supported : unit -> bool`
`val intersectionObserver : ((intersectionObserverEntry Js.t Js.js_array Js.t -> intersectionObserver Js.t -> unit) Js.callback -> intersectionObserverOptions Js.t -> intersectionObserver Js.t) Js.constr`