title: Android Play Billing Library: onSkuDetailsResponse responseCode is 0, but the size of skuDetailsList is also 0
body: <p>I'm now using the new Play Billing Library</p>
  
  <p>Basically, I followed the documentation to query available items to purchase</p>
  
  <pre><code> SkuDetailsParams.Builder params = SkuDetailsParams.newBuilder();
              params.setSkusList(skuList).setType(itemType);
              mBillingClient.querySkuDetailsAsync(params.build(),
                      new SkuDetailsResponseListener() {
  
                          @Override
                          public void onSkuDetailsResponse(int responseCode,
                                                           List&lt;SkuDetails&gt; skuDetailsList) {
                              listener.onSkuDetailsResponse(responseCode, skuDetailsList);
                          }
  </code></pre>
  
  <p>However, the responseCode is 0 and the list is also empty. But I checked onBillingSetupFinished is successful. The skuList that provided to SkuDetailsParams.Builder is not empty, and the values inside the skuList (sku_id) is also same as Product ID that specifies on Google Play Console. </p>
  
  <p>Does anyone know the reason? Thanks!!</p>