Attempt to create an instance of an interstitial ad.
If the instance is created successfully then the ad is preloaded ready for display in-game via the method
If the ad loads it will emit the
adloaded event, passing the AdInstance as the only parameter.
If the ad cannot be displayed because there was no inventory to fill it, it will emit the
|placementID||string | Array.<string>||
The ad placement ID, or an array of IDs, as created in your Audience Network settings within Facebook.
This Facebook Instant Games Plugin instance.