eliminate package dependency cycle

Change-Id: I7c30e5db9f5d17d24d28252b4dc58ce23835b6d8

@@ -4,8 +4,6 @@ import static com.google.common.base.Preconditions.checkNotNull;
 
 import java.util.Objects;
 
-import org.onlab.onos.net.link.LinkDescription;
-
 import com.google.common.base.MoreObjects;
 
 // TODO Consider renaming.
@@ -69,16 +67,6 @@ public final class LinkKey {
         return new LinkKey(link.src(), link.dst());
     }
 
-    /**
-     * Creates a link identifier for the specified link.
-     *
-     * @param desc link description
-     * @return a link identifier
-     */
-    public static LinkKey linkKey(LinkDescription desc) {
-        return new LinkKey(desc.src(), desc.dst());
-    }
-
     @Override
     public int hashCode() {
         return Objects.hash(src(), dst);

@@ -238,7 +238,7 @@ public class GossipLinkStore
 
         final Timestamped<LinkDescription> deltaDesc = new Timestamped<>(linkDescription, newTimestamp);
 
-        LinkKey key = linkKey(linkDescription);
+        LinkKey key = linkKey(linkDescription.src(), linkDescription.dst());
         final LinkEvent event;
         final Timestamped<LinkDescription> mergedDesc;
         synchronized (getLinkDescriptions(key)) {
@@ -265,7 +265,8 @@ public class GossipLinkStore
             ProviderId providerId,
             Timestamped<LinkDescription> linkDescription) {
 
-        LinkKey key = linkKey(linkDescription.value());
+        LinkKey key = linkKey(linkDescription.value().src(),
+                              linkDescription.value().dst());
         ConcurrentMap<ProviderId, Timestamped<LinkDescription>> descs = getLinkDescriptions(key);
 
         synchronized (descs) {

@@ -151,7 +151,7 @@ public class DistributedLinkStore
     @Override
     public LinkEvent createOrUpdateLink(ProviderId providerId,
                                         LinkDescription linkDescription) {
-        LinkKey key = linkKey(linkDescription);
+        LinkKey key = linkKey(linkDescription.src(), linkDescription.dst());
         Optional<DefaultLink> link = links.getUnchecked(key);
         if (!link.isPresent()) {
             return createLink(providerId, key, linkDescription);

@@ -149,7 +149,7 @@ public class SimpleLinkStore
     @Override
     public LinkEvent createOrUpdateLink(ProviderId providerId,
                                         LinkDescription linkDescription) {
-        LinkKey key = linkKey(linkDescription);
+        LinkKey key = linkKey(linkDescription.src(), linkDescription.dst());
 
         ConcurrentMap<ProviderId, LinkDescription> descs = getLinkDescriptions(key);
         synchronized (descs) {