Revert "Fixing Hosts filtered by RegionId... for topo-2 view."

This reverts commit 4aef6c371a5fd25171ef9ea8faf193d662c5544c.

Change-Id: Ib2959eb73686af2788525710e33f8fc8db78b819
diff --git a/core/store/dist/src/main/java/org/onosproject/store/region/impl/DistributedRegionStore.java b/core/store/dist/src/main/java/org/onosproject/store/region/impl/DistributedRegionStore.java
index 7e9a1a9b..e101514 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/region/impl/DistributedRegionStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/region/impl/DistributedRegionStore.java
@@ -27,6 +27,7 @@
 import org.onlab.util.Identifier;
 import org.onosproject.cluster.NodeId;
 import org.onosproject.net.DeviceId;
+import org.onosproject.net.HostId;
 import org.onosproject.net.region.DefaultRegion;
 import org.onosproject.net.region.Region;
 import org.onosproject.net.region.RegionEvent;
@@ -78,6 +79,7 @@
 
     private ConsistentMap<RegionId, Set<DeviceId>> membershipRepo;
     private Map<RegionId, Set<DeviceId>> regionDevices;
+    private Map<RegionId, Set<HostId>> regionHosts;
 
     private Map<DeviceId, Region> regionsByDevice = new HashMap<>();
 
@@ -90,7 +92,7 @@
     protected void activate() {
         Serializer serializer =
                 Serializer.using(Arrays.asList(KryoNamespaces.API),
-                        Identifier.class);
+                                 Identifier.class);
 
         regionsRepo = storageService.<RegionId, Region>consistentMapBuilder()
                 .withSerializer(serializer)
@@ -140,6 +142,12 @@
     }
 
     @Override
+    public Set<HostId> getRegionHosts(RegionId regionId) {
+        Set<HostId> hostIds = regionHosts.get(regionId);
+        return hostIds != null ? ImmutableSet.copyOf(hostIds) : ImmutableSet.of();
+    }
+
+    @Override
     public Region createRegion(RegionId regionId, String name, Region.Type type,
                                List<Set<NodeId>> masterNodeIds) {
         return regionsRepo.compute(regionId, (id, region) -> {
@@ -165,9 +173,8 @@
 
     @Override
     public void addDevices(RegionId regionId, Collection<DeviceId> deviceIds) {
-        // Devices can only be a member in one region.
-        // Remove the device if it belongs to a different region than
-        // the region for which we are attempting to add it.
+        // Devices can only be a member in one region.  Remove the device if it belongs to
+        // a different region than the region for which we are attempting to add it.
         for (DeviceId deviceId : deviceIds) {
             Region region = getRegionForDevice(deviceId);
             if ((region != null) && (!regionId.id().equals(region.id().id()))) {
@@ -201,7 +208,7 @@
             } else {
                 return ImmutableSet.<DeviceId>builder()
                         .addAll(Sets.difference(existingDevices,
-                                ImmutableSet.copyOf(deviceIds)))
+                                                ImmutableSet.copyOf(deviceIds)))
                         .build();
             }
         });
@@ -212,8 +219,7 @@
     /**
      * Listener class to map listener events to the region inventory events.
      */
-    private class InternalRegionListener
-            implements MapEventListener<RegionId, Region> {
+    private class InternalRegionListener implements MapEventListener<RegionId, Region> {
         @Override
         public void event(MapEvent<RegionId, Region> event) {
             Region region = null;
@@ -241,14 +247,13 @@
     /**
      * Listener class to map listener events to the region membership events.
      */
-    private class InternalMembershipListener
-            implements MapEventListener<RegionId, Set<DeviceId>> {
+    private class InternalMembershipListener implements MapEventListener<RegionId, Set<DeviceId>> {
         @Override
         public void event(MapEvent<RegionId, Set<DeviceId>> event) {
             if (event.type() != MapEvent.Type.REMOVE) {
                 notifyDelegate(new RegionEvent(REGION_MEMBERSHIP_CHANGED,
-                        regionsById.get(event.key()),
-                        event.newValue().value()));
+                                               regionsById.get(event.key()),
+                                               event.newValue().value()));
             }
         }
     }