H5 video全屏与取消全屏兼容

H5 video全屏与取消全屏各浏览器兼容，  requestFullscreen（）全屏方法，exitFullscreen()退出全屏方法。兼容各个浏览器与css3兼容一样加个前缀即可。

// 全屏
// ele:全屏的对象
function requestFullscreen(ele) {
    // 全屏兼容代码
    if (ele.requestFullscreen) {
        ele.requestFullscreen();
    } else if (ele.webkitRequestFullscreen) {
        ele.webkitRequestFullscreen();
    } else if (ele.mozRequestFullScreen) {
        ele.mozRequestFullScreen();
    } else if (ele.msRequestFullscreen) {
        ele.msRequestFullscreen();
    }
}

// 取消全屏
function exitFullscreen() {
    if (document.exitFullscreen) {
        document.exitFullscreen();
    } else if (document.webkitExitFullscreen) {
        document.webkitExitFullscreen();
    } else if (document.msExitFullscreen) {
        document.msExitFullscreen();
    } else if (document.mozCancelFullScreen) {
        document.mozCancelFullScreen();
    }
}