Simplify the use of the fee extension a little

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=133149148

java/google/registry/flows/domain/DomainCheckFlow.java

@@ -23,7 +23,6 @@ import static google.registry.model.index.DomainApplicationIndex.loadActiveAppli
 import static google.registry.model.registry.label.ReservationType.UNRESERVED;
 import static google.registry.pricing.PricingEngineProxy.getPricesForDomainName;
 import static google.registry.util.CollectionUtils.nullToEmpty;
-import static google.registry.util.DomainNameUtils.getTldFromDomainName;
 
 import com.google.common.base.Predicate;
 import com.google.common.collect.FluentIterable;
@@ -49,7 +48,6 @@ import google.registry.model.registry.label.ReservationType;
 import java.util.Collections;
 import java.util.Set;
 import javax.inject.Inject;
-import org.joda.money.CurrencyUnit;
 
 /**
  * An EPP flow that checks whether a domain can be provisioned.
@@ -160,7 +158,6 @@ public class DomainCheckFlow extends BaseDomainCheckFlow {
     if (feeCheck == null) {
       return null;  // No fee checks were requested.
     }
-    CurrencyUnit topLevelCurrency = feeCheck.isCurrencySupported() ? feeCheck.getCurrency() : null;
     ImmutableList.Builder<FeeCheckResponseExtensionItem> feeCheckResponseItemsBuilder =
         new ImmutableList.Builder<>();
     for (FeeCheckCommandExtensionItem feeCheckItem : feeCheck.getItems()) {
@@ -169,10 +166,9 @@ public class DomainCheckFlow extends BaseDomainCheckFlow {
         handleFeeRequest(
             feeCheckItem,
             builder,
-            domainName,
+            domainNames.get(domainName),
-            getTldFromDomainName(domainName),
             getClientId(),
-            topLevelCurrency,
+            feeCheck.getCurrency(),
             now,
             eppInput);
         feeCheckResponseItemsBuilder

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

@@ -564,14 +564,13 @@ public class DomainFlowUtils {
   static void handleFeeRequest(
       FeeQueryCommandExtensionItem feeRequest,
       FeeQueryResponseExtensionItem.Builder builder,
-      String domainName,
+      InternetDomainName domain,
-      String tld,
       String clientIdentifier,
       @Nullable CurrencyUnit topLevelCurrency,
       DateTime now,
       EppInput eppInput) throws EppException {
-    InternetDomainName domain = InternetDomainName.from(domainName);
+    String domainNameString = domain.toString();
-    Registry registry = Registry.get(tld);
+    Registry registry = Registry.get(domain.parent().toString());
     int years = verifyUnitIsYears(feeRequest.getPeriod()).getValue();
     boolean isSunrise = registry.getTldState(now).equals(TldState.SUNRISE);
 
@@ -580,7 +579,7 @@ public class DomainFlowUtils {
     }
 
     CurrencyUnit currency =
-        feeRequest.isCurrencySupported() ? feeRequest.getCurrency() : topLevelCurrency;
+        feeRequest.getCurrency() != null ? feeRequest.getCurrency() : topLevelCurrency;
     if ((currency != null) && !currency.equals(registry.getCurrency())) {
       throw new CurrencyUnitMismatchException();
     }
@@ -589,7 +588,7 @@ public class DomainFlowUtils {
         .setCommand(feeRequest.getCommandName(), feeRequest.getPhase(), feeRequest.getSubphase())
         .setCurrencyIfSupported(registry.getCurrency())
         .setPeriod(feeRequest.getPeriod())
-        .setClass(TldSpecificLogicProxy.getFeeClass(domainName, now).orNull());
+        .setClass(TldSpecificLogicProxy.getFeeClass(domainNameString, now).orNull());
 
     switch (feeRequest.getCommandName()) {
       case CREATE:
@@ -600,13 +599,13 @@ public class DomainFlowUtils {
         } else {
           builder.setAvailIfSupported(true);
           builder.setFees(TldSpecificLogicProxy.getCreatePrice(
-              registry, domainName, clientIdentifier, now, years, eppInput).getFees());
+              registry, domainNameString, clientIdentifier, now, years, eppInput).getFees());
         }
         break;
       case RENEW:
         builder.setAvailIfSupported(true);
         builder.setFees(TldSpecificLogicProxy.getRenewPrice(
-            registry, domainName, clientIdentifier, now, years, eppInput).getFees());
+            registry, domainNameString, clientIdentifier, now, years, eppInput).getFees());
         break;
       case RESTORE:
         if (years != 1) {
@@ -614,17 +613,17 @@ public class DomainFlowUtils {
         }
         builder.setAvailIfSupported(true);
         builder.setFees(TldSpecificLogicProxy.getRestorePrice(
-            registry, domainName, clientIdentifier, now, eppInput).getFees());
+            registry, domainNameString, clientIdentifier, now, eppInput).getFees());
         break;
       case TRANSFER:
         builder.setAvailIfSupported(true);
         builder.setFees(TldSpecificLogicProxy.getTransferPrice(
-            registry, domainName, clientIdentifier, now, years, eppInput).getFees());
+            registry, domainNameString, clientIdentifier, now, years, eppInput).getFees());
         break;
       case UPDATE:
         builder.setAvailIfSupported(true);
         builder.setFees(TldSpecificLogicProxy.getUpdatePrice(
-            registry, domainName, clientIdentifier, now, eppInput).getFees());
+            registry, domainNameString, clientIdentifier, now, eppInput).getFees());
         break;
       default:
         throw new UnknownFeeCommandException(feeRequest.getUnparsedCommandName());

java/google/registry/flows/domain/DomainInfoFlow.java

@@ -19,6 +19,7 @@ import static google.registry.flows.domain.DomainFlowUtils.handleFeeRequest;
 import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.net.InternetDomainName;
 import google.registry.flows.EppException;
 import google.registry.model.domain.DomainResource;
 import google.registry.model.domain.DomainResource.Builder;
@@ -97,8 +98,7 @@ public class DomainInfoFlow extends BaseDomainInfoFlow<DomainResource, Builder>
       handleFeeRequest(
           feeInfo,
           builder,
-          getTargetId(),
+          InternetDomainName.from(getTargetId()),
-          existingResource.getTld(),
           getClientId(),
           null,
           now,

java/google/registry/model/domain/fee/FeeCheckCommandExtension.java

@@ -33,11 +33,12 @@ public interface FeeCheckCommandExtension<
         R extends FeeCheckResponseExtension<?>>
     extends CommandExtension {
 
-  /** True if this version of the fee extension specifies the currency at the top level. */
+  /**
-  public boolean isCurrencySupported();
+   * Three-character ISO4217 currency code.
-
+   *
-  /** Three-character currency code; throws an exception if currency is not supported. */
+   * <p>Returns null if this version of the fee extension doesn't specify currency at the top level.
-  public CurrencyUnit getCurrency() throws UnsupportedOperationException;
+   */
+  public CurrencyUnit getCurrency();
 
   public ImmutableSet<C> getItems();
 

java/google/registry/model/domain/fee/FeeQueryCommandExtensionItem.java

@@ -35,11 +35,12 @@ public interface FeeQueryCommandExtensionItem {
     UPDATE
   }
 
-  /** True if this version of fee extension includes a currency in this type of query item. */
+  /**
-  public boolean isCurrencySupported();
+   * Three-character ISO4217 currency code.
-
+   *
-  /** A three-character ISO4217 currency code; throws an exception if currency is not supported. */
+   * <p>Returns null if this version of the fee extension doesn't specify currency at the top level.
-  public CurrencyUnit getCurrency() throws UnsupportedOperationException;
+   */
+  public CurrencyUnit getCurrency();
 
   /** The name of the command being checked. */
   public CommandName getCommandName();

java/google/registry/model/domain/fee06/FeeCheckCommandExtensionItemV06.java

@@ -40,11 +40,6 @@ public class FeeCheckCommandExtensionItemV06
     return name;
   }
 
-  @Override
-  public boolean isCurrencySupported() {
-    return true;
-  }
-
   @Override
   public CurrencyUnit getCurrency() {
     return currency;

java/google/registry/model/domain/fee06/FeeCheckCommandExtensionV06.java

@@ -36,14 +36,9 @@ public class FeeCheckCommandExtensionV06 extends ImmutableObject
   @XmlElement(name = "domain")
   Set<FeeCheckCommandExtensionItemV06> items;
 
-  @Override
-  public boolean isCurrencySupported() {
-    return false;
-  }
-
   @Override
   public CurrencyUnit getCurrency() {
-    throw new UnsupportedOperationException("Currency not supported");
+    return null;  // This version of the fee extension doesn't specify a top-level currency.
   }
 
   @Override

java/google/registry/model/domain/fee06/FeeInfoCommandExtensionV06.java

@@ -29,11 +29,6 @@ public class FeeInfoCommandExtensionV06
   /** A three-character ISO4217 currency code. */
   CurrencyUnit currency;
 
-  @Override
-  public boolean isCurrencySupported() {
-    return true;
-  }
-
   @Override
   public CurrencyUnit getCurrency() {
     return currency;

java/google/registry/model/domain/fee11/FeeCheckCommandExtensionV11.java

@@ -60,14 +60,12 @@ public class FeeCheckCommandExtensionV11 extends ImmutableObject
   @XmlElement(name = "class")
   String feeClass;
 
-  @Override
-  public boolean isCurrencySupported() {
-    return false;
-  }
-  
   @Override
   public CurrencyUnit getCurrency() {
-    throw new UnsupportedOperationException("Currency not supported");
+    // This version of the fee extension does not have any items, and although the currency is
+    // specified at the top level we've modeled it as a single fake item with the currency inside,
+    // so there's no top level currency to return here.
+    return null;  
   }
 
   @Override
@@ -130,11 +128,6 @@ public class FeeCheckCommandExtensionV11 extends ImmutableObject
       throw new UnsupportedOperationException("Domain not supported");
     }
 
-    @Override
-    public boolean isCurrencySupported() {
-      return true;
-    }
-
     @Override
     public CurrencyUnit getCurrency() {
       return currency;

java/google/registry/model/domain/fee12/FeeCheckCommandExtensionItemV12.java

@@ -76,14 +76,9 @@ public class FeeCheckCommandExtensionItemV12
     throw new UnsupportedOperationException("Domain not supported");
   }
 
-  @Override
-  public boolean isCurrencySupported() {
-    return false;
-  }
-  
   @Override
   public CurrencyUnit getCurrency() {
-    throw new UnsupportedOperationException("Currency not supported");
+    return null;  // This version of the fee extension doesn't specify currency per-item.
   }
 
   @Override

java/google/registry/model/domain/fee12/FeeCheckCommandExtensionV12.java

@@ -37,11 +37,6 @@ public class FeeCheckCommandExtensionV12 extends ImmutableObject
 
   CurrencyUnit currency;
 
-  @Override
-  public boolean isCurrencySupported() {
-    return true;
-  }
-
   @Override
   public CurrencyUnit getCurrency() {
     return currency;