Fixed issue with canonicalization of link identifiers.
- added asId() to LinkKey
- BiLink.linkId() now returns LinkKey.asId()

Change-Id: Ie9069ca5302f09fca9e213ce33fa87bd8868e752
diff --git a/core/api/src/main/java/org/onosproject/ui/topo/BiLink.java b/core/api/src/main/java/org/onosproject/ui/topo/BiLink.java
index 16e8dc5..b50e34d 100644
--- a/core/api/src/main/java/org/onosproject/ui/topo/BiLink.java
+++ b/core/api/src/main/java/org/onosproject/ui/topo/BiLink.java
@@ -38,7 +38,7 @@
      * that the caller will have used {@link TopoUtils#canonicalLinkKey(Link)}
      * to generate the key.
      *
-     * @param key canonical key for this bi-link
+     * @param key  canonical key for this bi-link
      * @param link first link
      */
     public BiLink(LinkKey key, Link link) {
@@ -62,7 +62,7 @@
      * @return link identifier
      */
     public String linkId() {
-        return TopoUtils.compactLinkString(one);
+        return key.asId();
     }
 
     /**
@@ -92,6 +92,11 @@
         return two;
     }
 
+    @Override
+    public String toString() {
+        return key.asId();
+    }
+
     /**
      * Returns the link highlighting to use, based on this bi-link's current
      * state.