Add additional specific PricingEngineProxy methods

We already had methods to return just the create or just the renew price. I added more to return just the premium flag or just the fee class.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=136833071

java/google/registry/flows/domain/DomainFlowUtils.java

@@ -27,7 +27,7 @@ import static google.registry.model.EppResourceUtils.loadByForeignKey;
 import static google.registry.model.ofy.ObjectifyService.ofy;
 import static google.registry.model.registry.Registries.findTldForName;
 import static google.registry.model.registry.label.ReservedList.getReservation;
-import static google.registry.pricing.PricingEngineProxy.getPricesForDomainName;
+import static google.registry.pricing.PricingEngineProxy.isDomainPremium;
 import static google.registry.tldconfig.idn.IdnLabelValidator.findValidIdnTableForTld;
 import static google.registry.util.CollectionUtils.nullToEmpty;
 import static google.registry.util.DateTimeUtils.END_OF_TIME;
@@ -413,7 +413,7 @@ public class DomainFlowUtils {
    */
   static void verifyPremiumNameIsNotBlocked(
       String domainName, DateTime priceTime, String clientId) throws EppException {
-    if (getPricesForDomainName(domainName, priceTime).isPremium()) {
+    if (isDomainPremium(domainName, priceTime)) {
       // NB: The load of the Registar object is transactionless, which means that it should hit
       // memcache most of the time.
       if (Registrar.loadByClientId(clientId).getBlockPremiumNames()) {
@@ -686,7 +686,7 @@ public class DomainFlowUtils {
       throws EppException {
     Registry registry = Registry.get(tld);
     if (registry.getPremiumPriceAckRequired()
-        && getPricesForDomainName(domainName, priceTime).isPremium()
+        && isDomainPremium(domainName, priceTime)
         && feeCommand == null) {
       throw new FeesRequiredForPremiumNameException();
     }