getOneTimeOffers
Returns every offer attached to a one-time (INAPP) product, mapped to a typed OneTimeOfferInfo.
Play Billing 9 lets a one-time product carry multiple offers — a full price plus, say, a 30%-off launch discount, a rental, or a pre-order. The legacy getOneTimePurchaseOfferDetails exposes only one of them; this returns the full list.
Return
Immutable List of offers (never null). Empty when the product is a subscription or its details are not loaded.
Since
4.4.0
Parameters
productId
One-time product id.