title: querySkuDetailsAsync is returning empty list with BillingResult code SERVICE_UNAVAILABLE
body: <p>After upgrading the BillingClient to 3.0.0, I started getting about 20% users seeing <code>SERVICE_UNAVAILABLE</code> when querying for in-app purchase. The skuDetailsList is also empty. According to the docs, <code>SERVICE_UNAVAILABLE</code> implies network is down, but how is the client returning <code>OK</code> with the <code>startConnection</code> and sending this after trying to query the SKU details? Additionally, I'm seeing a few <code>ERROR</code>, which is code 6. Did I have some incorrect implementation or do I just show the user some &quot;An error occurred. Try later&quot; message? I also don't see any warning for any countries in the Play Console or anything that may cause this.</p>
  <pre><code>BillingClient billingClient = BillingClient.newBuilder(getContext())
              .enablePendingPurchases()
              .setListener((billingResult, list) -&gt; {})
              .build();
  
      mBillingClient.startConnection(new BillingClientStateListener() {
          @Override
          public void onBillingSetupFinished(@NonNull BillingResult billingResult) {
              if (billingResult.getResponseCode() == BillingClient.BillingResponseCode.OK) {
                  createSkus(mBillingClient);
              }
          }
  
          @Override
          public void onBillingServiceDisconnected() {}
      });
  
  
  private void createSkus(BillingClient billingClient) {
      List&lt;String&gt; skuList = new ArrayList&lt;&gt;();
      skuList.add(&quot;pro&quot;);
      SkuDetailsParams.Builder params = SkuDetailsParams.newBuilder();
      params.setSkusList(skuList).setType(BillingClient.SkuType.INAPP);
      billingClient.querySkuDetailsAsync(params.build(),
              (billingResult, skuDetailsList) -&gt; {
                  // skuDetailsList empty with BillingResult code 2 (SERVICE_UNAVAILABLE)
  
                  BillingFlowParams billingFlowParams = BillingFlowParams.newBuilder()
                          .setSkuDetails(skuDetailsList.get(0))
                          .build();
                  billingClient.launchBillingFlow(activity, billingFlowParams);
              });
  }
  </code></pre>