@Override
            public String description() {
              return "regionQueue not empty with size " + regionQueue.size() + " for proxy "
                  + proxy;
            }
This is to test the serialization mechanism of ClientUpdateMessage. Added after CQ support.
This could be done in different way, by overflowing the HARegion queue.
geode-cq/src/distributedTest/java/org/apache/geode/internal/cache/ha/HADispatcherDistributedTest.java