private static void add(SignalQueue queue, int from, int to) {
        for (int i = from; i < to; i++) {
            queue.addAndRemoveIfRequested(httpData(i));
        }
    }
A test for the {@link SignalQueue} in {@link DefaultStreamMessageDuplicator}.
Queue expansion behaves differently when odd/even number head wrap-around happens.
core/src/test/java/com/linecorp/armeria/common/stream/StreamMessageDuplicatorTest.java