Method AsyncSink

okhttp/src/main/java/io/grpc/okhttp/AsyncSink.java:65–70

(SerializingExecutor executor, TransportExceptionHandler exceptionHandler,
      int maxQueuedControlFrames)

  private int queuedControlFrames;

  private AsyncSink(SerializingExecutor executor, TransportExceptionHandler exceptionHandler,
      int maxQueuedControlFrames) {
    this.serializingExecutor = checkNotNull(executor, "executor");
    this.transportExceptionHandler = checkNotNull(exceptionHandler, "exceptionHandler");
    this.maxQueuedControlFrames = maxQueuedControlFrames;
  }

  /**
   * {@code maxQueuedControlFrames} is only effective for frames written with