Add asynchronous scheduled actions to re-save entities

This is used in the domain transfer and delete flows, both of which are
asynchronous flows that have implicit default actions that will be taken at some
point in the future. This CL adds scheduled re-saves to take place soon after
those default actions would become effective, so that they can be re-saved
quickly if so.

Unfortunately the redemption grace period on our TLDs is 35 days, which exceeds
the 30 day maximum task ETA in App Engine, so these won't actually fire.  That's
fine though; the deletion is actually effective as of 5 days, and this is just
removing the grace period.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=201345274

java/google/registry/flows/domain/DomainTransferRequestFlow.java

@@ -42,6 +42,7 @@ import google.registry.flows.FlowModule.Superuser;
 import google.registry.flows.FlowModule.TargetId;
 import google.registry.flows.TransactionalFlow;
 import google.registry.flows.annotations.ReportingSpec;
+import google.registry.flows.async.AsyncFlowEnqueuer;
 import google.registry.flows.exceptions.AlreadyPendingTransferException;
 import google.registry.flows.exceptions.InvalidTransferPeriodValueException;
 import google.registry.flows.exceptions.ObjectAlreadySponsoredException;
@@ -125,6 +126,7 @@ public final class DomainTransferRequestFlow implements TransactionalFlow {
   @Inject @Superuser boolean isSuperuser;
   @Inject HistoryEntry.Builder historyBuilder;
   @Inject Trid trid;
+  @Inject AsyncFlowEnqueuer asyncFlowEnqueuer;
   @Inject EppResponse.Builder responseBuilder;
   @Inject DomainPricingLogic pricingLogic;
   @Inject DomainTransferRequestFlow() {}
@@ -224,6 +226,7 @@ public final class DomainTransferRequestFlow implements TransactionalFlow {
         .setTransferData(pendingTransferData)
         .addStatusValue(StatusValue.PENDING_TRANSFER)
         .build();
+    asyncFlowEnqueuer.enqueueAsyncResave(newDomain, now, automaticTransferTime);
     ofy().save()
         .entities(new ImmutableSet.Builder<>()
             .add(newDomain, historyEntry, requestPollMessage)