void pollOpManager(List<RequestInfo> requestsToSend, Set<Integer> requestsToDrop) {
      switch (opType) {
        case PUT:
          putManager.poll(requestsToSend, requestsToDrop);
          break;
        case GET:
          getManager.poll(requestsToSend, requestsToDrop);
          break;
        case DELETE:
          deleteManager.poll(requestsToSend, requestsToDrop);
          break;
      }
    }
Poll the associated operation manager.
@param requestsToSend the list of {@link RequestInfo} to send to pass into the poll call.
@param requestsToDrop the list of correlation IDs to drop to pass into the poll call.
ambry-router/src/test/java/com/github/ambry/router/NonBlockingRouterTestBase.java