public void RestoreTransactions(Action <bool> callback)
 {
     m_GooglePlayStoreService.FetchPurchases(purchase =>
     {
         if (purchase != null)
         {
             callback(true);
         }
     });
 }
 public void FetchPurchases()
 {
     m_GooglePlayStoreService.FetchPurchases(OnFetchedPurchase);
 }