Move DroppedEventListener out of kafka domain

DroppedEventListener is not kafka specific so it should be move to
multi-site engine

Feature: Issue 10829
Change-Id: I7c43bb5b14dd323bc72fb8e855aee377b56f7171
diff --git a/src/main/java/com/googlesource/gerrit/plugins/multisite/consumer/SubscriberModule.java b/src/main/java/com/googlesource/gerrit/plugins/multisite/consumer/SubscriberModule.java
index 940ad1f..0a0c350 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/multisite/consumer/SubscriberModule.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/multisite/consumer/SubscriberModule.java
@@ -32,5 +32,6 @@
     listener().to(MultiSiteConsumerRunner.class);
 
     DynamicSet.setOf(binder(), AbstractSubcriber.class);
+    DynamicSet.setOf(binder(), DroppedEventListener.class);
   }
 }
diff --git a/src/main/java/com/googlesource/gerrit/plugins/multisite/kafka/KafkaBrokerModule.java b/src/main/java/com/googlesource/gerrit/plugins/multisite/kafka/KafkaBrokerModule.java
index be57b18..5fdb07e 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/multisite/kafka/KafkaBrokerModule.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/multisite/kafka/KafkaBrokerModule.java
@@ -23,7 +23,6 @@
 import com.googlesource.gerrit.plugins.multisite.broker.kafka.KafkaSession;
 import com.googlesource.gerrit.plugins.multisite.consumer.AbstractSubcriber;
 import com.googlesource.gerrit.plugins.multisite.consumer.CacheEvictionEventSubscriber;
-import com.googlesource.gerrit.plugins.multisite.consumer.DroppedEventListener;
 import com.googlesource.gerrit.plugins.multisite.consumer.IndexEventSubscriber;
 import com.googlesource.gerrit.plugins.multisite.consumer.ProjectUpdateEventSubscriber;
 import com.googlesource.gerrit.plugins.multisite.consumer.SourceAwareEventWrapper;
@@ -68,8 +67,6 @@
       if (config.kafkaSubscriber().enabledEvent(EventTopic.PROJECT_LIST_TOPIC)) {
         DynamicSet.bind(binder(), AbstractSubcriber.class).to(ProjectUpdateEventSubscriber.class);
       }
-
-      DynamicSet.setOf(binder(), DroppedEventListener.class);
     }
 
     if (config.kafkaPublisher().enabled()) {