Sets any necessary internal data when setting up IAP for this platform. Currently this only applies to Google Play and Ouya where you need to provide your public key in base64. This must be called before InAppPurchaseSetup.
To find the public key for Google Play apps, open your application's details in the Google PlayDeveloper Console, and click Services & APIs. The public key will be in the box titled "Your license key for this application".
InAppPurchaseSetKeys ( szData1, szData2 )