final void writeData(HttpData data) {
        data.touch(ctx);
        logBuilder.increaseRequestLength(data);
        write(data, data.isEndOfStream());
    }
Writes the {@link HttpData} to the {@link Channel}.
Note that the written data is not flushed by this method. The caller should explicitly call
{@link Channel#flush()} when each write unit is done.
core/src/main/java/com/linecorp/armeria/client/AbstractHttpRequestHandler.java