Start implementation of new billing

[jamesmontemagno]

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Fixes # .

Changes Proposed in this pull request:

[Dexus]

Hi @jamesmontemagno you should be sure to use the latest Goole Billing API (v3.0) if not your app will rejected and not published anymore also your app will removed from the playstore. So my question now is Xamarin.Android.Google.BillingClient 3.0 equivalent to API 3.0?

Best regards, Josef

[jamesmontemagno]

yeah, we already updated to 3.0.

Also, that is different that is for the server, not in the app. it is confusing.

[Dexus]

yeah, we already updated to 3.0.

Also, that is different that is for the server, not in the app. it is confusing.

Thanks for the info.

[dmariogatto]

I noticed that the signature of GetPurchasesAsync has changed to no longer accept an instance of IInAppBillingVerifyPurchase. Is there a reason restoring previous purchases no longer requires validation?

[jamesmontemagno]

It exists,

Task<IEnumerable<InAppBillingPurchase>> GetPurchasesAsync(ItemType itemType);

It no longer requires verification as it wasn't adding value at all in the implementation. You can still verify and just call it yourself. I don't want to be in control of your verification process.