Function create_buffer_source 

pub(crate) fn create_buffer_source<T>(
    cx: JSContext,
    data: &[T::Element],
    dest: MutableHandleObject<'_>,
    _can_gc: CanGc,
) -> Result<RootedTraceableBox<TypedArray<T, Box<Heap<*mut JSObject>>>>, ()>
where
    T: TypedArrayElement + TypedArrayElementCreator,

https://webidl.spec.whatwg.org/#arraybufferview-create