Code review comment for lp:~vanvugt/mir/always-triple-buffers

It is at least documented already:

    /**
     * Set the minimum number of smooth frames the client must keep up with
     * the compositor for in order to qualify for queue scaling (dynamic
     * double buffering for reduced latency). A negative value means never
     * but it's recommended that you never change this.
     */
    void set_scaling_delay(int nframes);