code: public void consumeAsync(Purchase purchase, OnConsumeFinishedListener listener) {
          checkNotDisposed();
          checkSetupDone("consume");
          List<Purchase> purchases = new ArrayList<Purchase>();
          purchases.add(purchase);
          consumeAsyncInternal(purchases, listener, null);
      }
docs: Asynchronous wrapper to item consumption. Works like {@link #consume}, but
  performs the consumption in the background and notifies completion through
  the provided listener. This method is safe to call from a UI thread.
  
  @param purchase The purchase to be consumed.
  @param listener The listener to notify when the consumption operation finishes.