Adding device and host tracking for intents (ONOS-1356)

Also, this should fix ONOS-1184 (intents submitted before hosts detected).

Change-Id: I47a503c18dc728912132eb2e2fcc160d47e518eb
diff --git a/core/api/src/main/java/org/onosproject/net/intent/HostToHostIntent.java b/core/api/src/main/java/org/onosproject/net/intent/HostToHostIntent.java
index 157397a..01ef54d 100644
--- a/core/api/src/main/java/org/onosproject/net/intent/HostToHostIntent.java
+++ b/core/api/src/main/java/org/onosproject/net/intent/HostToHostIntent.java
@@ -15,15 +15,14 @@
  */
 package org.onosproject.net.intent;
 
-import java.util.Collections;
-import java.util.List;
-
+import com.google.common.base.MoreObjects;
+import com.google.common.collect.ImmutableSet;
 import org.onosproject.core.ApplicationId;
 import org.onosproject.net.HostId;
 import org.onosproject.net.flow.TrafficSelector;
 import org.onosproject.net.flow.TrafficTreatment;
 
-import com.google.common.base.MoreObjects;
+import java.util.List;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
@@ -147,7 +146,7 @@
                             TrafficTreatment treatment,
                             List<Constraint> constraints,
                             int priority) {
-        super(appId, key, Collections.emptyList(), selector, treatment,
+        super(appId, key, ImmutableSet.of(one, two), selector, treatment,
               constraints, priority);
 
         // TODO: consider whether the case one and two are same is allowed