Fix NPE when getting the callback cookie.

Was using the wrong method to fetch the cookie.

Test: runtest frameworks-services -c com.android.server.NetworkScoreServiceTest
Bug: 34987725
Change-Id: Iba26086e52ded98c4bf2ea5f9b5d7d6abfe88c20

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

@@ -927,7 +927,7 @@ public class NetworkScoreService extends INetworkScoreService.Stub {
                 try {
                     for (int i = 0; i < count; i++) {
                         consumer.accept(callbackList.getBroadcastItem(i),
-                                callbackList.getRegisteredCallbackCookie(i));
+                                callbackList.getBroadcastCookie(i));
                     }
                 } finally {
                     callbackList.finishBroadcast();