track
Asynchronously registers an impression - a reasonable expectation that a user has seen a piece of content - with Marigold SPM. Can be used in conjunction with RecyclerView.Adapter#onViewAttachedToWindow or similar to know when a particular content item has entered the user's viewport.
Parameters
section
the Section ID on Marigold SPM corresponding to the section being viewed. Must not be null.
urls
a List of the URLs of the items contained within this section. Useful if multiple items of content are contained within a section, otherwise just pass a single-item array. May be null.
handler
an instance of TrackHandler. May be null, in which case onSuccess and onFailure callbacks won't be fired.