Notify registrars of async contact/host deletions

We now send PendingActionNotificationResponses in our poll messages upon completion of an asynchronous contact or host deletion. This is part 1 of 2, which begins logging Trid in all enqueued Host/Contact deletion flows for use in batch deletions, and optionally consuming the resultant Trid info to emit a Host/ContactPendingActionNotifcationResponse.

Part 2 will make this response emission non-optional, which will happen once the queue is cleared of all non-Trid containing tasks.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=153084197

java/google/registry/model/poll/PendingActionNotificationResponse.java

@@ -125,4 +125,30 @@ public abstract class PendingActionNotificationResponse
           processedDate);
     }
   }
+
+  /** An adapter to output the XML in response to resolving a pending command on a host. */
+  @Embed
+  @XmlRootElement(name = "panData", namespace = "urn:ietf:params:xml:ns:domain-1.0")
+  @XmlType(
+    propOrder = {"name", "trid", "processedDate"},
+    namespace = "urn:ietf:params:xml:ns:domain-1.0"
+  )
+  public static class HostPendingActionNotificationResponse
+      extends PendingActionNotificationResponse {
+
+    @XmlElement
+    NameOrId getName() {
+      return nameOrId;
+    }
+
+    public static HostPendingActionNotificationResponse create(
+        String fullyQualifiedHostName, boolean actionResult, Trid trid, DateTime processedDate) {
+      return init(
+          new HostPendingActionNotificationResponse(),
+          fullyQualifiedHostName,
+          actionResult,
+          trid,
+          processedDate);
+    }
+  }
 }