Fix a bug where updates of offers won't find existing offers

.equals() only work on cross-process Binder instances if casted to
a Binder instance first.

Bug: 184281544
Test: ConnectivityServiceTest. CTS test for this specific issue to come
Change-Id: I7b9e0df21a3cca59659867a75792289ddee2f1d7

services/core/java/com/android/server/ConnectivityService.java

@@ -6601,7 +6601,7 @@ public class ConnectivityService extends IConnectivityManager.Stub
             @NonNull final INetworkOfferCallback callback) {
         ensureRunningOnConnectivityServiceThread();
         for (final NetworkOfferInfo noi : mNetworkOffers) {
-            if (noi.offer.callback.equals(callback)) return noi;
+            if (noi.offer.callback.asBinder().equals(callback.asBinder())) return noi;
         }
         return null;
     }

services/core/java/com/android/server/connectivity/NetworkOffer.java

@@ -133,7 +133,7 @@ public class NetworkOffer implements NetworkRanker.Scoreable {
      * @param previousOffer the previous offer
      */
     public void migrateFrom(@NonNull final NetworkOffer previousOffer) {
-        if (!callback.equals(previousOffer.callback)) {
+        if (!callback.asBinder().equals(previousOffer.callback.asBinder())) {
             throw new IllegalArgumentException("Can only migrate from a previous version of"
                     + " the same offer");
         }