2.x: Workaround for Objects.requireNonNull inserted by javac (#5966)

Author: akarnokd

src/test/java/io/reactivex/processors/UnicastProcessorTest.java

@@ -430,7 +430,7 @@ public void alreadyCancelled() {
     public void unicastSubscriptionBadRequest() {
         UnicastProcessor<Integer> us = UnicastProcessor.create(false);
 
-        UnicastProcessor<Integer>.UnicastQueueSubscription usc = us.new UnicastQueueSubscription();
+        UnicastProcessor<Integer>.UnicastQueueSubscription usc = (UnicastProcessor<Integer>.UnicastQueueSubscription)us.wip;
 
         List<Throwable> errors = TestHelper.trackPluginErrors();
         try {