Scope down lastTransferTime to only ContactResource, DomainResource

and HostResource.

DomainApplication is not transferable and has no need for this
field. HostResource needs it because it can be transferred with
a domain.

This is all in service of removing the ofy().load() inside of
host's cloneProjectedAtTime.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=139346925

java/google/registry/model/domain/DomainApplication.java

@@ -185,13 +185,6 @@ public class DomainApplication extends DomainBase {
     return auctionPrice;
   }
 
-  /** Domain applications don't expose transfer time, so override this and mark it xml transient. */
-  @XmlTransient
-  @Override
-  public final DateTime getLastTransferTime() {
-    return super.getLastTransferTime();
-  }
-
   /**
    * The application id is the repoId.
    */