Make name and address fields required on Registrar

The absence of these fields causes RDE failures, so they are in effect
required on any functioning registry system. We are currently
experiencing problems in sandbox caused by null values on these fields.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155474895

java/google/registry/whois/DomainWhoisResponse.java

@@ -66,7 +66,11 @@ final class DomainWhoisResponse extends WhoisResponseImpl {
 
   @Override
   public WhoisResponseResults getResponse(final boolean preferUnicode, String disclaimer) {
-    Registrar registrar = getRegistrar(domain.getCurrentSponsorClientId());
+    Registrar registrar =
+        checkNotNull(
+            Registrar.loadByClientId(domain.getCurrentSponsorClientId()),
+            "Could not load registrar %s",
+            domain.getCurrentSponsorClientId());
     Optional<RegistrarContact> abuseContact =
         Iterables.tryFind(
             registrar.getContacts(),