Save the RDAP request time globally instead of passing it around

Also removed the rdapWhoisServer value, as it's just null and will likely stay that way (it isn't mentioned in the RDAP response profile)

If it'll ever become required, we can add it back.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=247643981

java/google/registry/rdap/RdapDomainAction.java

@@ -31,7 +31,6 @@ import google.registry.request.HttpException.NotFoundException;
 import google.registry.request.auth.Auth;
 import java.util.Optional;
 import javax.inject.Inject;
-import org.joda.time.DateTime;
 
 /** RDAP (new WHOIS) action for domain requests. */
 @Action(
@@ -48,7 +47,6 @@ public class RdapDomainAction extends RdapActionBase {
 
   @Override
   public RdapDomain getJsonObjectForResource(String pathSearchString, boolean isHeadRequest) {
-    DateTime now = clock.nowUtc();
     pathSearchString = canonicalizeName(pathSearchString);
     try {
       validateDomainName(pathSearchString);
@@ -61,14 +59,14 @@ public class RdapDomainAction extends RdapActionBase {
     // The query string is not used; the RDAP syntax is /rdap/domain/mydomain.com.
     Optional<DomainBase> domainBase =
         loadByForeignKey(
-            DomainBase.class, pathSearchString, shouldIncludeDeleted() ? START_OF_TIME : now);
-    if (!shouldBeVisible(domainBase, now)) {
+            DomainBase.class,
+            pathSearchString,
+            shouldIncludeDeleted() ? START_OF_TIME : rdapJsonFormatter.getRequestTime());
+    if (!shouldBeVisible(domainBase)) {
       throw new NotFoundException(pathSearchString + " not found");
     }
     return rdapJsonFormatter.makeRdapJsonForDomain(
         domainBase.get(),
-        rdapWhoisServer,
-        now,
         OutputDataType.FULL);
   }
 }