ReplaySubjectConcurrencyTest > testReplaySubjectConcurrentSubscriptions FAILED

[akarnokd]

rx.subjects.ReplaySubjectConcurrencyTest > testReplaySubjectConcurrentSubscriptions FAILED
    java.lang.RuntimeException: Concurrency Bug
        at rx.subjects.ReplaySubjectConcurrencyTest.testReplaySubjectConcurrentSubscriptions(ReplaySubjectConcurrencyTest.java:235)

[akarnokd]

New crash type:

rx.subjects.ReplaySubjectConcurrencyTest > testReplaySubjectConcurrentSubscriptions FAILED
    java.lang.NullPointerException
        at rx.subjects.ReplaySubjectConcurrencyTest.testReplaySubjectConcurrentSubscriptions(ReplaySubjectConcurrencyTest.java:221)

[akarnokd]

Fixed via #4051.