scrollTop doesn't scroll on Chrome 61

在chrome61 不支持滚动 解决方案：

Use document.scrollingElement if supported, and fall back to the current code.

For example, if the current (problematic) code is something like:

function bodyOrHtml() => {
	if (navigator.userAgent.indexOf(‘WebKit‘) != -1) {
		return document.body;
	}
	return document.documentElement;
}
...
bodyOrHtml().scrollTop = 100;

下面是最好的解决方法：

function bodyOrHtml() => {
	if (‘scrollingElement‘ in document) {
		return document.scrollingElement;
	}
	// Fallback for legacy browsers
	if (navigator.userAgent.indexOf(‘WebKit‘) != -1) {
		return document.body;
	}
	return document.documentElement;
}
...
bodyOrHtml().scrollTop = 100;

参考：https://dev.opera.com/articles/fixing-the-scrolltop-bug/

scrollTop doesn't scroll on Chrome 61