VideoPlayerCtrl `onVideoPlayerEvent` CLICKED 事件需要判断是否全屏

[DreamZhou]

如果全屏状态, 无法暂停.

        if (event === cc.VideoPlayer.EventType.CLICKED) {
            if (!this.videoPlayer.isFullscreen) {   // <------ 需要加此判断
                if (this.videoPlayer.isPlaying()) {
                    this.videoPlayer.pause();
                } else {
                    this.videoPlayer.play();
                }
            }
        }