Add metric for DNS UPDATE latency

Added:
- dns/update_latency, which measures the time since a DNS update was added to the pull queue until that updates is committed to the DnsWriter
- - It doesn't check that after being committed, it was actually published in the DNS.

- dns/publish_queue_delay, which measures how long since the initial insertion to the push queue until a publishDnsUpdate action was handled. It measures both for successes (which is what we care about) and various failures (which are important because the success for that publishDnsUpdate will be > than any of the previous failures)

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=185995678

java/google/registry/dns/DnsModule.java

@@ -19,7 +19,10 @@ import static google.registry.dns.DnsConstants.DNS_PULL_QUEUE_NAME;
 import static google.registry.dns.PublishDnsUpdatesAction.PARAM_DNS_WRITER;
 import static google.registry.dns.PublishDnsUpdatesAction.PARAM_DOMAINS;
 import static google.registry.dns.PublishDnsUpdatesAction.PARAM_HOSTS;
+import static google.registry.dns.PublishDnsUpdatesAction.PARAM_PUBLISH_TASK_ENQUEUED;
+import static google.registry.dns.PublishDnsUpdatesAction.PARAM_REFRESH_REQUEST_CREATED;
 import static google.registry.request.RequestParameters.extractEnumParameter;
+import static google.registry.request.RequestParameters.extractOptionalParameter;
 import static google.registry.request.RequestParameters.extractRequiredParameter;
 import static google.registry.request.RequestParameters.extractSetOfParameters;
 
@@ -32,9 +35,11 @@ import google.registry.dns.DnsConstants.TargetType;
 import google.registry.dns.writer.DnsWriterZone;
 import google.registry.request.Parameter;
 import google.registry.request.RequestParameters;
+import java.util.Optional;
 import java.util.Set;
 import javax.inject.Named;
 import javax.servlet.http.HttpServletRequest;
+import org.joda.time.DateTime;
 
 /** Dagger module for the dns package. */
 @Module
@@ -56,6 +61,20 @@ public abstract class DnsModule {
     return QueueFactory.getQueue(DNS_PUBLISH_PUSH_QUEUE_NAME);
   }
 
+  @Provides
+  @Parameter(PARAM_PUBLISH_TASK_ENQUEUED)
+  // TODO(b/73343464): make the param required once the transition has finished
+  static Optional<DateTime> provideCreateTime(HttpServletRequest req) {
+    return extractOptionalParameter(req, PARAM_PUBLISH_TASK_ENQUEUED).map(DateTime::parse);
+  }
+
+  @Provides
+  @Parameter(PARAM_REFRESH_REQUEST_CREATED)
+  // TODO(b/73343464): make the param required once the transition has finished
+  static Optional<DateTime> provideItemsCreateTime(HttpServletRequest req) {
+    return extractOptionalParameter(req, PARAM_REFRESH_REQUEST_CREATED).map(DateTime::parse);
+  }
+
   @Provides
   @Parameter(PARAM_DNS_WRITER)
   static String provideDnsWriter(HttpServletRequest req) {