Cleaned up some of the host-related abstractions and filled in more of the host manager implementation.
diff --git a/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleDeviceManager.java b/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleDeviceManager.java
index 17d3aa0..c322b70 100644
--- a/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleDeviceManager.java
+++ b/core/trivial/src/main/java/org/onlab/onos/net/trivial/impl/SimpleDeviceManager.java
@@ -51,7 +51,7 @@
     private final AbstractListenerRegistry<DeviceEvent, DeviceListener>
             listenerRegistry = new AbstractListenerRegistry<>();
 
-        private final SimpleDeviceStore store = new SimpleDeviceStore();
+    private final SimpleDeviceStore store = new SimpleDeviceStore();
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected EventDeliveryService eventDispatcher;
@@ -110,21 +110,6 @@
     }
 
     @Override
-    public void addListener(DeviceListener listener) {
-        listenerRegistry.addListener(listener);
-    }
-
-    @Override
-    public void removeListener(DeviceListener listener) {
-        listenerRegistry.removeListener(listener);
-    }
-
-    @Override
-    protected DeviceProviderService createProviderService(DeviceProvider provider) {
-        return new InternalDeviceProviderService(provider);
-    }
-
-    @Override
     public void setRole(DeviceId deviceId, MastershipRole newRole) {
         checkNotNull(deviceId, DEVICE_ID_NULL);
         checkNotNull(newRole, ROLE_NULL);
@@ -149,6 +134,21 @@
         }
     }
 
+    @Override
+    public void addListener(DeviceListener listener) {
+        listenerRegistry.addListener(listener);
+    }
+
+    @Override
+    public void removeListener(DeviceListener listener) {
+        listenerRegistry.removeListener(listener);
+    }
+
+    @Override
+    protected DeviceProviderService createProviderService(DeviceProvider provider) {
+        return new InternalDeviceProviderService(provider);
+    }
+
     // Personalized device provider service issued to the supplied provider.
     private class InternalDeviceProviderService extends AbstractProviderService<DeviceProvider>
             implements DeviceProviderService {