EthernetDataTracker: Start DHCP on Link Up

The behavior of mLinkUp has previously changed so that it only
represents the link state.  This changes fixes
interfaceLinkStateChanged() so that it triggers a reconnect based
only on the present link state.

Change-Id: I950e04e1f5b5019d59d3b9530f369f8b8f13134a
Signed-off-by: Adam Hampson <ahampson@google.com>

core/java/android/net/EthernetDataTracker.java

@@ -74,7 +74,7 @@ public class EthernetDataTracker implements NetworkStateTracker {
         }
 
         public void interfaceLinkStateChanged(String iface, boolean up) {
-            if (mIface.equals(iface) && mLinkUp != up) {
+            if (mIface.equals(iface)) {
                 Log.d(TAG, "Interface " + iface + " link " + (up ? "up" : "down"));
                 mLinkUp = up;
                 mTracker.mNetworkInfo.setIsAvailable(up);