Merge pull request ReactiveX#3370 from artem-zinnatullin/remove-unused-field-updater-from-SubjectSubscriptionManager

Remove unused field updater from SubjectSubscriptionManager

Author: stevegury

src/main/java/rx/subjects/SubjectSubscriptionManager.java

@@ -40,8 +40,6 @@
             = AtomicReferenceFieldUpdater.newUpdater(SubjectSubscriptionManager.class, State.class, "state");
     /** Stores the latest value or the terminal value for some Subjects. */
     volatile Object latest;
-    static final AtomicReferenceFieldUpdater<SubjectSubscriptionManager, Object> LATEST_UPDATER
-            = AtomicReferenceFieldUpdater.newUpdater(SubjectSubscriptionManager.class, Object.class, "latest");
     /** Indicates that the subject is active (cheaper than checking the state).*/
     boolean active = true;
     /** Action called when a new subscriber subscribes but before it is added to the state. */